Secondary structural analysis of the mRNA regions encoding the hemagglutinin cleavage site basic amino acids of the avian influenza virus H5N1 subtype samples

Here we report the codon bias and the mRNA secondary structural features of the hemagglutinin (HA) cleavage site basic amino acid regions of avian influenza virus H5N1 subtypes. We have developed a dynamic extended folding strategy to predict RNA secondar

Cloning and expression of zebra fish ferroportin and investigating its influence on anemia

Iron is required for many microbes and pathogens for their survival and proliferation including Leishmania which cause leishmaniasis. Leishmaniasis is an increasingly serious infectious disease with a wide spectrum of clinical manifestations. These range from localized cutaneous leishmaniasis (CL) lesions to a lethal visceral form. Certain strains such as BALB/c mice fail to control L. major infection and develop progressive lesions and systemic disease. These mice are thought to be a model of non-healing forms of the human disease such as kala-azar or diffuse cutaneous leishmaniasis. Progression of disease in BALB/c mice has been associated with the anemia, in last days of their survival, the progressive anemia is considered to be one of the reasons of their death. Ferroportin (Fpn), a key regulator of iron homeostasis is a conserved membrane protein that exports iron across the duodenal enterocytes as well as macrophages and hepatocytes into the blood circulation. Fpn has also critical influence on survival and proliferation of many microorganisms whose growth is dependent upon iron, thus preparation of Fpn is needed to study the role of iron in immune responses and pathogenesis of micoorganisms. To prepare and characterize a recombinant ferroportin, total RNA was extracted from Indian zebrafish duodenum, and used to synthesize cDNA by RT-PCR. PCR product was first cloned in Topo TA vector and then subcloned into the GFP expression vector pEGFP–N1. The final resulted plasmid (pEGFP-ZFpn) was used for expression of FPN-EGFP protein in Hek 293T cells. The expression was confirmed by fluorescence microscopy and flow cytometery. Recombinant Fpn was further characterized by submission of its predicted amino acid sequences to the TMHMM V2.0 prediction server (hidden Markov model), NetOGlyc 3.1 server and NetNGlyc 3.1 server. Data emphasised that obtained Fpn from indian zebrafish contained eight transmembrane domains with N- and C-termini inside the cytoplasm and harboured 78 mucin-type glycosylated amino acid. The results indicate that the prepared and characterized recombinant Fpn protein has no membrane topology difference compared to other Fpn described by other researcher. Our next aim was to deliver recombinant plasmid (pEGFP-ZFpn) to entrocyte cells. However, naked therapeutic genes are rapidly degraded by nucleases, showing poor cellular uptake, nonspecificity to the target cells, and low transfection efficiency. The development of safe and efficient gene carriers is one of the prerequisites for the success of gene therapy. Chitosan and alginate 139 polymers were used for oral gene carrier because of their biodegradability, biocompatibility and their mucoadhesive and permeability-enhancing properties in the gut. Nanoparticles comprising Alginate/Chitosan polymers were prepared by pregel preparation method. The resulting nanoparticles had a loading efficiency of 95% and average size of 188 nm as confirmed by PCS method and SEM images had showed spherical particles. BALB/c mice were divided to three groups. The first and second group were fed with chitosan/alginate nanoparticles containing the pEGFP-ZFpn and pEGFP plasmid, respectively (30 μgr/mice) and the third group (control) didn’t get any nanoparticles. The result showed BALB/c mice infected by L.major, resulted in higher hematocryte and iron level in pEGFP-ZFpn fed mice than that in other groups. Consentration of cytokines determined by ELISA showed lower levels of IL-4 and IL-10 and higher levels of IFN-γ/IL-4 and IFN-γ/IL-10 ratios in pEGFP-ZFpn fed mice than that in other groups. Morover more limited increase of footpad thickness and significant reduction of viable parasites in lymph node was seen in pEGFP-ZFpn fed mice. The results showed the first group exhibited a highr hematocryte and iron compared to the other groups. These data strongly suggests the in vivo administration of chitosan/alginate nanoparticles containing pEGFP-ZFpn suppress Th2 response and may be used to control the leishmaniasis .

Effect of amino acids on cryopreservation of cynomolgus monkey (Macaca fascicularis) sperm

The effects of three amino acids (proline, glutamine, and glycine) added to the freezing medium Tes-Tris-egg yolk (TTE) for cryopreservation of cynomolgus monkey (Macaca fascicularis) spermatozoa were studied. This is the first report on the effects of amino acids on nonhuman primate sperm cryopreservation. The addition of 5 mM proline, 10 mM glutamine, and 10 or 20 mM glycine each significantly improved post-thaw sperm motility and membrane and acrosome integrity compared with the control (TTE alone). However, a significant decrease in motility and membrane/acrosome integrity was observed when amino acid concentrations increased to 60 mM for proline and glutamine, and 80 mM for glycine. The results suggest that adding a limited amount of amino acids to the freezing media is beneficial for freezing cynomolgus monkey sperm.

Effects of aniracetam on extracellular levels of transmitter amino acids in the hippocampus of the conscious gerbils: an intracranial microdialysis study

The effects of aniracetam on extracellular amino acid levels in the hippocampus of conscious gerbils, with or without transient cerebral ischemia/reperfusion, were measured by microdialysis and reverse phase-high performance liquid chromatography. Increased extracellular levels of aspartate and glutamate that were observed in the hippocampus of conscious gerbils during transient global forebrain ischemia were reversed by aniracetam. In contrast, the level of extracellular gamma-aminobutyric acid was increased, while taurine was maintained at a higher level than other amino acids by administration of aniracetam (100 mg/kg, p.o.) 60 min before ischemia. Further, in contrast to ischemic animals, administration of aniracetam (100 mg/kg, p.o.) enhanced the release of glutamate and aspartate in the normal gerbil hippocampus. The results suggest that these effects might be due to a partial calcium agonist activity of aniracetam, and that the effects of aniracetam on amino acid levels might be a mechanism of protection against delayed neuronal death in the ischemic hippocampus, thereby improving memory dysfunction induced by ischemia/reperfusion. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved.

Genome-wide identification and characterization of cytochrome P450 monooxygenase genes in the ciliate Tetrahymena thermophila

Background: Cytochrome P450 monooxygenases play key roles in the metabolism of a wide variety of substrates and they are closely associated with endocellular physiological processes or detoxification metabolism under environmental exposure. To date, however, none has been systematically characterized in the phylum Ciliophora. T. thermophila possess many advantages as a eukaryotic model organism and it exhibits rapid and sensitive responses to xenobiotics, making it an ideal model system to study the evolutionary and functional diversity of the P450 monooxygenase gene family. Results: A total of 44 putative functional cytochrome P450 genes were identified and could be classified into 13 families and 21 sub-families according to standard nomenclature. The characteristics of both the conserved intron-exon organization and scaffold localization of tandem repeats within each P450 family clade suggested that the enlargement of T. thermophila P450 families probably resulted from recent separate small duplication events. Gene expression patterns of all T. thermophila P450s during three important cell physiological stages (vegetative growth, starvation and conjugation) were analyzed based on EST and microarray data, and three main categories of expression patterns were postulated. Evolutionary analysis including codon usage preference, sit-especific selection and gene-expression evolution patterns were investigated and the results indicated remarkable divergences among the T. thermophila P450 genes. Conclusion: The characterization, expression and evolutionary analysis of T. thermophila P450 monooxygenase genes in the current study provides useful information for understanding the characteristics and diversities of the P450 genes in the Ciliophora, and provides the baseline for functional analyses of individual P450 isoforms in this model ciliate species.

Kinetic study of the 2-methyl-3-methoxy-4-phenylbutanoic acid produced by oxidation of microcystin in aqueous solutions

Microcystins (MCs) are a family of related cyclic hepatotoxic heptapeptides, of which more than 70 types have been identified. The chemically unique nature of the C20 beta-amino acid, (2S, 3S, 8S, 9S)-3-amino-9-methoxy-2,6,8-trimethyl-10-phenyldeca4,6-dienoic acid (Adda), portion of the MCs has been exploited to develop a strategy to analyze the entirety. Oxidation of MCs causes the cleavage of MC Adda to form 2-methyl-3-methoxy-4-phenylbutanoic acid (MMPB). In the present study, we investigated the kinetics of MMPB produced by oxidation of the most-often-studied MC variant, MC-LR (L = leucine, R = arginine), with permanganate-periodate. This investigation allowed insight regarding the influence of the reaction conditions (concentration of the reactants, temperature, and pH) on the conversion rate. The results indicated that the reaction was second order overall and first order with respect to both permanganate and MC-LR. The second-order rate constant ranged from 0.66 to 1.35 M/s at temperatures from 10 to 30 degrees C, and the activation energy was 24.44 kJ/mol. The rates of MMPB production can be accelerated through increasing reaction temperature and oxidant concentration, and sufficient periodate is necessary for the formation of MMPB. The initial reaction rate under alkaline and neutral conditions is higher than that under acidic conditions, but the former decreases faster than the latter except under weakly acidic conditions. These results provided new insight concerning selection of the permanganate-periodate concentration, pH, and temperature needed for the oxidation of MCs with a high and stable yield of MMPB.

Effects of ammonium on growth, nitrogen and carbohydrate metabolism of Potamogeton maackianus A. Benn

Growth, nitrogen and carbohydrate metabolism in relation to eutrophication were studied for a submerged plant Potamogeton maackianus, a species common in East Asian shallow lakes. The plants were grown in six NH4+-N concentrations (0.05, 0.50, 1.00, 3.50, 5.00 and 10.00 mg/L) for six days. NH4+-N levels in excess of 0.50 mg/L inhibited the plant growth. The relationships between external NH4+-N availability and total nitrogen (TN), protein-N, free amino acid-N (FAA-N) and NH4+-N in plant tissues, respectively, conformed to a logarithmic model suggesting that a feedback inhibition mechanism may exist for ammonium uptake. The response of starch to NH4+-N was fitted with a negative, logarithmic curve. Detailed analysis revealed that the influx NH4+-N had been efficiently incorporated into organic-N and eventually stored as protein at the expense of starch accumulation. These data suggest that this species may be able to tolerate high levels of ammonium when dissolved oxygen is sufficient.

Expression pattern and developmental behaviour of cellular nucleic acid-binding protein (CNBP) during folliculogenesis and oogenesis in fish

In vertebrates, folliculogeneis establishes an intricate system for somatic cell-oocyte interaction, and ultimately leads to the acquisition of their respective competences. Although the formation process and corresponding interactions are strikingly similar in diverse organisms, knowledge of genes and signaling pathways involved in follicle formation is very incomplete and the underlying molecular mechanisms remain enigmatic. CNBP has been identified for more than ten years, and the highest level of CNBP transcripts has been observed in adult zebrafish ovary, but little is known about its functional significance during folliculogeneis and oogenesis. In this study, we clone CNBP cDNA from gibel carp (Carassius auratus gibelio), and demonstrate its predominant expression in gibel carp ovary and testis not only by RTPCR but also by Western blot. Its full-length cDNA is 1402 bp, and has an ORF of 489 nt for encoding a peptide of 163 aa. And its complete amino acid sequence shared 68.5%-96.8% identity with CNBPs from other vertebrates. Based on the expression characterization, we further analyze its expression pattern and developmental behaviour during folliculogeneis and oogenesis. Following these studies, we reveal an unexpected discovery that the CagCNBP is associated with follicular cells and oocytes, and significant distribution changes have occurred in degenerating and regenerating follicles. More interestingly, the CagCNBP is more highly expressed in some clusters of interconnected cells within ovarian cysts, no matter whether the cell clusters are formed from the original primordial germ cells or from the newly formed cells from follicular cells that invaded into the atretic oocytes. It is the first time to reveal CNBP relevance to folliculogeneis and oogenesis. Moreover, a similar stage-specific and cell-specific expression pattern has also been observed in the gibel carp testis. Therefore, further studies on CNBP expression pattern and developmental behaviour will be of significance for understanding functional roles of CNBP during gametogenests. (c) 2005 Elsevier B.V. All rights reserved.

Characterization of two genes encoding leucine-rich repeat-containing proteins in grass carp Ctenopharyngodon idellus

The cDNAs and genes of two different types of leucine- rich repeat-containing proteins from grass carp ( Ctenopharyngodon idellus) were cloned. Homology search revealed that the two genes, designated as GC-GARP and GC-LRG, have 37% and 32% deduced aminoacid sequence similarities with human glycoprotein A repetitions predominant precursor ( GARP) and leucine-rich alpha2-glycoprotein (LRG), respectively. The cDNAs of GC-GARP and GC-LRG encoded 664 and 339 amino acid residues, respectively. GC-GARP and GC-LRG contain many distinct structural and/or functional motifs of the leucine- rich repeat (LRR) subfamily, such as multiple conserved 11-residue segments with the consensus sequence LxxLxLxxN/CxL ( x can be any amino acid). The genes GC-GARP and GC-LRG consist of two exons, with 4,782 bp and 2,119 bp in total length, respectively. The first exon of each gene contains a small 5'-untranslated region and partial open reading frame. The putative promoter region of GC-GARP was found to contain transcription factor binding sites for GATA-1, IRF4, Oct-1, IRF-7, IRF-1, AP1, GATA-box and NFAT, and the promoter region of GC-LRG for MYC-MAX, MEIS1, ISRE, IK3, HOXA9 and C/EBP alpha. Phylogenetic analysis showed that GC-GARP and mammalian GARPs were clustered into one branch, while GC-LRG and mammalian LRGs were in another branch. The GC-GARP gene was only detected in head kidney, and GC-LRG in the liver, spleen and heart in the copepod ( Sinergasilus major)- infected grass carp, indicating the induction of gene expression by the parasite infection. The results obtained in the present study provide insight into the structure of fish LRR genes, and further study should be carried out to understand the importance of LRR proteins in host - pathogen interactions.

硫手性有机小分子催化剂的设计、合成及其在不对称亚胺氢转移还原中的应用

过去十多年，世界手性药物市场需求迅速增长，手性制药工业的发展壮大，已经引起了各国政府、学术界，特别是企业界的高度重视。手性药物中含有大量的手性胺单元，因此研究高效构建手性胺结构单元的方法具有重要的意义和实用价值，而亚胺的不对称还原是合成手性胺最便捷的方法。 手性有机小分子路易斯碱催化三氯氢硅不对称还原亚胺是最近几年才发展起来的一类新的亚胺不对称还原方法。尽管在对映选择性和底物适用范围等方面已经获得了突破性的进展，但是，高性能的路易斯碱催化剂仅局限于N-甲酰氨基酸酰胺一种类型，而且其底物适用范围和催化活性仍不够理想。因此，发展新型催化剂很有必要。 手性硫氧化物作为手性诱导剂的应用已经有数十年的时间，广泛应用在不对称合成及天然产物的全合成中。理论上，硫氧结构单元也可以作为路易斯碱，对硅烷类试剂进行活化，而且硫氧键还有碳氧键难以比拟的先天优势，硫原子自带手性特征，在反应过程中，手性中心离反应位点更近，因此，从手性硫氧化合物出发，极有可能开发出新的高效手性路易斯碱催化剂。最近，Kobayashi和Khiar在亚胺的不对称烯丙基化反应中用手性亚砜活化烯丙基三氯硅烷，获得了较好的ee值，但反应中手性亚砜的用量都需要化学计量以上，因此还不能算做真正意义上的催化剂，进一步的文献调研也未见真正意义上的硫手性有机小分子催化剂。 本文首次成功将硫手性亚磺酰胺衍生物应用于催化三氯氢硅对亚胺的不对称还原，在经过对亚磺酰胺衍生物的多次结构优化，开发出了合成容易，催化活性和立体选择性都很优良，并且有着前所未有的底物普适性的新型手性路易斯碱催化剂。 我们首先尝试将商品化的20mol%叔丁基亚磺酰胺和对甲基亚磺酰胺直接用作催化剂催化三氯氢硅对亚胺的不对称还原，尽管仅获得中等的收率和很低的对映选择性，但证明我们的设计思路是可行的。在此基础上，我们以叔丁基亚磺酰胺为原料和基本骨架，设计合成了一系列的亚磺酰胺类催化剂，通过对催化剂的结构改造，发现当催化剂中存在较强酸性的酚羟基时，催化效果得到大幅提高。随着对催化剂的进一步结构优化，我们找到了一个结构简单，催化效果还不错的催化剂，经过反应条件优化以后，催化反应的收率最高能达到98%，对映选择性最高达93%，并且这个催化剂的底物适应范围比之前报道的催化剂都要广泛。针对酚羟基在催化剂中的重要作用，我们进行了仔细的机理研究后发现，在催化反应中，催化剂极有可能是通过双分子机理去活化三氯氢硅从而实现不对称催化的，而酚羟基的作用就是通过分子间氢键促进双分子催化剂与三氯氢硅的络合。受此启发，我们设计了一系列具有双齿结构的催化剂，通过对双齿催化剂的结构优化，最终筛选出了一个结构更加简单，但催化效果更好的双齿催化剂。10mol%该催化剂催化亚胺还原最高获得95%的收率和96%的ee值。这一结果也进一步验证了我们先前对催化剂机理的推测。 随后，我们还尝试将这些催化剂用于二级胺和芳香酮的直接还原胺化反应中，虽然能获得不错的收率，但对映选择性却很差，我们对反应条件进行了仔细的摸索，仍然没有获得突破。但这些实验为进一步研究二级胺和酮的不对称直接还原胺化反应奠定了良好的基础。 In the past decade, the rapid growth of the global chiral drug market and the significant development of the chiral pharmaceutical industry have attracted a great deal of attention from government, academia and enterprises. Chiral amine is an important structural motif of chiral drugs. Therefore, development of methods for the construction of this motif is of great importance. Catalytic enantioselective reduction of imines represents one of the most straightforward and efficient methods for the preparation of chiral amines. The chiral Lewis base organocatalysts promoted asymmetric reduction of imines by HSiCl3 has recently achieved significant advancements. Although big breakthroughs have been made in terms of substrate generality and enantioselectivity, the highly effective catalysts are limited to N-formyl amino acid amides, of which the efficiency and substrate scope remain unsatisfactory. Therefore, development of novel organocatalysts for this transformation is in great demand. Chiral sulfoxides have been well established as efficient and versatile stereocontrollers and have been extensively used in asymmetric synthesis and total synthesis of natural products. The S=O structural motif of sulfoxide could also behave as Lewis base activator for cholorsilane reagents, which, moreover, could be even better than caboxamide considering that the sulfur atom is chiral and thus the chirality center is closer to the reaction center. There exist great potentials that highly effective novel Lewis base organocatalysts could be developed starting from S-chiral sulfoxides. Recently, several S-chiral sulfoxides were reported by Kobayashi and Khiar to be used as Lewis base catalyst to activate allyltrichlorosilanes in asymmetric allylations and good enantioselectivities were obtained. However, these S-chiral sulfoxides were all used at a more than stoichiometric amount and were thus not authentically catalytic. A careful literature survey further revealed that there has been so far no S-chiral organocatalyst available. In this study, we, for the first time, successfully used S-chiral sulfinamides as Lewis base organocatalysts for the asymmetric reduction of ketimines by HSiCl3. After several rounds of structural optimization, we developed the first example of highly effective S-chiral organocatalysts, which promoted the asymmetric reduction of ketimines with trichlorosilane in high yield and excellent enantioselectivity with unprecedented substrate spectrum. In our initial practice, we examined 20mol% of the commercially available (R)-tert-butanesulfinamide and (S)-toluenesulfinamide as the catalyst in the hydrosilylation of ketimine. Although the product was only furnished in moderate yield and low ee, these results demonstrated that our strategy of catalyst design is on the right way. Next, starting from chiral tert-butanesulfinamide, we prepared a series of tert-butanesulfinamide derivatives via simple reductive amination and examined their catalytic efficiencies in the reduction of ketimine. We found that the catalyst bearing a phenolic hydroxyl group exhibited good reactivity and enantioselectivity. On the basis of which, we obtained a structurally simple and highly effective novel organocatalyst, affording the product in 98% yield and 93% ee under optimal reaction conditions. After careful exploration on the role of phenolic hydroxyl group in the catalyst, we speculated that two molecules of the catalyst be involved in the course of reaction, of which the assembly around the silicon center is facilitated by the intermolecular hydrogen bonding through the phenolic hydroxyl groups. Thus, we incorporated two units of sulfonamide into one molecular and prepared a new type of bissulfinamides organocatalysts and examined their catalytic efficiencies in the reduction of ketimine. After optimizing the structure of these catalysts, we finally obtained a novel organocatalyst which has even simpler molecular structure but showed better efficacies, 10mol% of which afforded up to 97% yield and 96% ee under optimal reaction conditions. These results further proved our speculation about the catalytic mechanism. We also examined the newly developed S-chiral organocatalysts in direct asymmetric reductive amination of secondary amines with aromatic ketone. The product was furnished in good yield but in low ee. No better results could be obtained despite our intense opimization efforts. Nevertheless, these experiments laid excellent foundations for eventual success.

青稞B组醇溶蛋白基因与上游调控区的克隆及基因表达

高等植物种子胚乳贮藏蛋白是种子发芽时的主要氮源，也是人类和动物食用植物蛋白的主要来源。大麦种子胚乳贮藏蛋白主要是醇溶蛋白（hordeins），占大麦胚乳总蛋白的50–60%。根据大麦醇溶蛋白的大小和组成特点，大麦醇溶蛋白被划分为三种类型：富硫蛋白亚类(B，γ-hordeins)、贫硫蛋白亚类（C-hordeins)以及高分子量蛋白亚类(D-hordeins)。B组和C组醇溶蛋白是大麦胚乳的两类主要贮藏蛋白，它们分别占大麦总醇溶蛋白成分的70–80%和10–12%。遗传分析表明，大麦B、C、D和γ-组醇溶蛋白分别是由位于大麦第五染色体1H（5）上的Hor2、Hor1、Hor3和Hor5位点编码。Hor2位点编码大量分子量相同但组成不同的B组醇溶蛋白（B-hordein）。B-hordein的种类、数量和分布是影响大麦酿造、食用及饲养品质的重要因素之一。为深入了解B-hordein基因家族的结构和染色体组织，探明Hor2位点基因表达的发育调控机制，最终达到改良禾谷类作物籽粒品质的目的，本研究以青藏高原青稞为材料，采用同源克隆法，分别克隆B-hordein基因和启动子，通过原核生物表达验证B-hordein基因功能，并利用实时定量PCR探索B-hordein基因表达时空关系，取得如下研究结果： 1. 以具有特殊B组醇溶蛋白亚基组成的9份青藏高原青稞为材料，根据GenBank中三个B-hordein基因序列（GenBank No. X03103, X53690和X53691）设计一对引物，通过PCR扩增，获得23个B-hordein基因克隆并对其进行了序列分析。核苷酸序列分析表明，所有克隆均包含完整的开放阅读框。有11个克隆都存在一个框内终止密码子，推测这11个克隆可能是假基因。推测的氨基酸序列分析表明，所有大麦B-hordein具有相似的蛋白质基本结构，均包括一个高度保守的信号肽、中间重复区以及C-端结构域。不同大麦种重复区内重复基元的数目有较大差异。青稞材料Z07–2和Z26的B-hordeins仅具有12个重复基元结构，更接近于野生大麦。这些重复基元数目的差异导致了重复区序列长度和结构的变异。这种现象极可能是由于醇溶谷蛋白基因在进化过程中染色体的不平衡交换或复制滑动所造成的。对所克隆基因和禾本科代表性醇溶谷蛋白基因进行聚类分析，结果表明所有来自栽培大麦的B-hordeins聚类成一个亚家族，来自野生大麦的B-hordeins以及普通小麦的LMW-GS聚类成另外一个亚家族，表明这两个亚家族的成员存在显著差异。此外，我们发现B-hordein基因推测的C-末端序列具有一些有规律的特征：即具有相同C-末端序列的B-hordein基因在系统发生树中聚类为同一个亚组（除BXQ053，BZ09-1，BZ26-5分别单独聚为一类外）。这个特征将有助于我们对所有B组醇溶蛋白基因家族成员进行分类，避免了在SDS-PAGE电泳图谱上仅依靠大小分类的局限性。 2. 根据上述克隆的青稞B-hordein基因的5’端序列设计三条基因特异的反向引物，以青稞Z09和Z26的基因组DNA为模板，采用SON-PCR和TAIL-PCR技术分离克隆出8个B-hordein基因的上游调控序列（命名为Z09P和Z26P）。序列分析表明，推测的TATA box位于–80 bp，CAAT–like box位于–140 bp处。此外，Z09P和Z26P中有六个序列在–300 bp处均存在一个由高度保守的EM基序和类GCN4基序构成的胚乳盒(Endosperm Box，EB)，在约–560 bp处存在一个胚乳盒类似结构。而Z09P-2和Z26P-3不存在保守的胚乳盒或其类似结构，预示着这两个启动子所调控的基因表达可能受不同类型反式作用因子的调节，推测该启动子对基因的表达调控具有多样性。 3. 将B-hordein基因的开放阅读框定向克隆到表达载体pET-30a中，将其导入大肠杆菌表达菌株BL21中进行外源基因的诱导表达以验证所克隆基因的功能。结果表明仅含重组子pET-BZ07-2和pET-BZ26-5的BL21细菌有目的表达蛋白产生。在诱导3 h时的蛋白表达量最高；3 mM IPTG诱导的蛋白表达量要高于1 mM IPTG诱导的表达量。这为分离纯化B-hordein蛋白以及进一步研究其对大麦籽粒品质的影响奠定基础。 4. 根据从青稞Z09和Z26中分离克隆的B-hordein基因序列设计一对基因特异的引物，同时，选择大麦α-微管蛋白基因（GenBank no. U40042）为看家基因并设计特异引物，利用实时荧光定量PCR检测了青稞籽粒4个胚乳发育时间段的B-hordein基因表达，荧光定量结果显示：两份材料中B-hordein基因的表达量均随发育过程的进行而逐渐升高。Z09中B-hordein基因在开花后7天开始转录，而Z26开花4天后就有低水平B-hordein的表达，这表明Z26中B-hordein基因可能比Z09表达的较早或者Z09中B-hordein基因表达水平较低以致于不能被检测到。此外，在4个不同的胚乳发育时期中，Z26中B-hordein基因的表达量均高于Z09材料。在开花12天到18天的过程中，Z09和Z26中B-hordein基因的表达水平有一个急剧性的升高。这说明在不同胚乳发育时期，Hor2位点的B-hordein等位基因变异体存在mRNA的差异表达。 Seed endosperm storage proteins in higher plants are the main resources of nitrogen for germinating and plant proteins for human and animals. Barley prolamins (also called hordeins) are the major storage proteins in the endosperm and account for 50–60% of total proteins. Hordeins are classically divided into three groups: sulphur-rich (B, γ-hordeins), sulphur-poor (C-hordeins) and high molecular weight (HMW, D-hordeins) hordeins based on the size and composition. B-hordeins and C-hordeins are two major groups and each respectively account for about 70-80% and 10-12% of the total hordein fraction in barley endosperm. Genetic analysis showed that B-, C-, C-, γ-hordeins are encoded by Hor2, Hor1, Hor3 and Hor5 locus on the chromosome 1H (5). Hor2 locus is rich in alleles that encode numerous heterogeneous B-hordein polypeptides. It is reported that B-hordein species, quantity and distribution are significant factors affecting malting, food and feed quality of barley. To understand comprehensively the structure and organization of B-hordein gene family in hull-less barley and explore the developmental control mechanisms of Hor2 locus gene expression and eventually to better exploitation in crop grain quality improvement, we isolated and cloned B-hordein genes and promotors of hull-less barley from Qinghai-Tibet Plateau by PCR, and testified their expression founction in bacteria expression system and explore their spatial and temporal expression pattern by quantitative real time PCR. Our results are as followed, 1. Twenty-three copies of B-hordein gene were cloned from nine hull-less barley cultivars of Qinghai-Tibet Plateau with special B-hordein subunits and molecularly characterized by PCR, based on three B-hordein genes published previously (GenBank No. X03103, X53690 and X53691). DNA sequences analyses confirmed that the six clones all contained a full-length coding region of the barley B-hordein genes. Eleven clones all contain an in-frame stop codon and they are probably pseudogenes. The analysis of deduced amino acid sequences of the genes shows that they have similar structures including signal peptide domain, central repetitive domain, and C-terminal domain. The number of the repeats was largerly variable and resulted in polypeptides in different sizes or structures among the genes. Twelve such repeated motifs were found in Z07–2 and Z26, and they are close to those of the wild barleys, and it is most probably caused by unequal crossing-over and/or slippage during replication as suggested for the evolution of other prolamins. The relatedness of prolamin genes of barley and wheat was assessed in the phylogenetic tree based on their polypeptides comparison. Our phylogenetic analysis suggested that the predicted B-hordeins of cultivated barley formed a subfamily, while the B-hordeins of wild barleys and the two most similar sequences of LMW-GS of T. aestivum formed another subfamily. This result indicated that the members of the two subfamilys have a distinctive difference. In addition, we found the B-hordeins with identical C-terminal end sequences were clustered into a same subgroup (except BXQ053，BZ09-1 and BZ26-5 as a sole group, respectively), so we believe that B-hordein gene subfamilies possibly can be classified on the basis of the conserved C-terminal end sequences of predicted polypeptide and without the limit of SDS-PAGE protein banding patterns. 2. The specific primers were designed according to the published sequences of barley B-hordein genes from Z09 and Z26. Using total DNA isolated from them as the templates, eight clones (designated Z09Pand Z26P) of upstream sequences of the known B-hordein genes was obtained by TAIL-PCR and SON-PCR. Sequences analysis shows that the putative TATA box was present at position –80 bp and CAAT-like box at position –140 bp. Besides, a putative Endosperm Box including an Endosperm Motif (EM) and a GCN4-Like Motif was found at position –300 bp in six clones, and another Endosperm-like box was found at positon –560 bp. While the Endosperm Box or Endosperm-like box was not found in Z09P-2 and Z26P-3. This may indicate that gene expression drived by the two promtors was probably controlled by different trans-acting factors and the genetic control mechanism of corresponding gene expression may be diverse. 3. The B-hordein genic region coding for the mature peptide was cloned into expression vector pET-30a and transformed into bacterial strain BL21 for identifying gene expression fountion. Protein SDS–PAGE analysis showed that only the transformed lysate with the pET-BZ07-2 and pET-BZ26-5 constructs produced proteins related to B-group hordeins of barley, and the mounts of proteins induced by 3 mM IPTG and 3 h were higher than other conditions. This established a base for isolating and putifying B-hordein and further exploring their effects on barley grain quality. 4. The gene-specific primers of B-hordein genes from Z09 and Z26 were used for the quantification of B-hordein gene expression. The α-tubulin gene from Hordeum vulgare subsp. vulgare (GenBank accession number U40042) was used as a control gene. The result shows the transcription of the B-hordein genes in Z09 was found 7 days after flowering, while the transcription of the B-hordein genes in Z26 was found 4 days after flowering, but at a very low level, and it suggested that the B-hordein genes in Z26 probably expressed earlier than those in Z09, or the B-hordein genes in Z09 expressed at so a lower level than Z26 that it can not detected. In addition, B-hordein genes in Z26 accession showed higher expression levels than those in Z09 in four developing stages. Furthermore, a progressive increase in the expression levels of the B-hordein genes between 12 and 18 days after anthesis was observed in both Z09 and Z26. It implies that the B-hordein allelic variants encoded by Hor2 locus exist the differential expression in mRNA levels of during barley endosperm development.

来自易变山羊草抗禾谷孢囊线虫基因的克隆与序列分析

禾谷孢囊线虫（Heterodera avenae）是严重危害禾谷类作物的病原线虫之一,它广泛分布于澳大利亚、欧洲、北美、印度和中国等世界主要小麦产区,使作物严重减产,造成巨大的经济损失。目前最有效的防治措施之一是将外源抗性基因导入栽培小麦(Triticum aestivum L.)，培育抗禾谷孢囊线虫的新品种。但迄今为止抗禾谷孢囊线虫基因克隆研究的相关报道却很少。 本实验根据此前从抗禾谷孢囊线虫材料E-10扩增得到的与来自节节麦（Aegilops tauschii）的抗禾谷孢囊线虫基因Cre3高度同源的序列Rccn4,设计出三条嵌套引物,采用SON-PCR(single oligonucleotide nested PCR)方法,从E-10基因组DNA中得到一个长为1264 bp的扩增产物(命名为Rccn-L),测序比对结果显示,这一序列将Rccn4的3’端延伸了1209 bp,与抗禾谷孢囊线虫Cre3基因核苷酸同源性为86﹪，核苷酸编码区长1026 bp，含一个不完整的开放阅读框,一个终止密码子，没有起始密码子和内含子结构,编码一个342个氨基酸残基的蛋白质。该蛋白质等电点为5.19，分子量为38112.6Da。从序列的第113位开始到第332位是NBS-LRR类抗病性基因LRR区,呈现XXLXXLXXL重复。LRR编码区内亮氨酸残基的含量达17﹪，与抗禾谷孢囊线虫Cre3基因LRR编码区的核苷酸和氨基酸同源性分别为89﹪和78﹪。本实验首次将SON-PCR成功地运用于植物基因克隆，为植物基因克隆提供了又一有效方法。 此外,还根据Cre3基因及其他的NBS-LRR类植物抗性基因的NBS和LRR区保守序列设计了两对特异性引物，从禾谷孢囊线虫抗性材料易变山羊草基因组DNA中扩增到两个相应的目标条带。测序分析结果表明，它们的长度分别为532bp和1175bp，构成了一个有32bp的共同序列的NBS-LRR编码区。其序列总长为1675bp（命名为RCCN），含有一个不完整的开放阅读框，没有起始密码子、终止密码子和内含子结构。其中编码序列为1673bp，可编码一个557个氨基酸的蛋白质，等电点（pI）为5.39，分子量为63537.5Da。与Cre3的核苷酸和氨基酸同源性分别为87.8﹪和77﹪。RCCN氨基酸序列中含有已知抗病基因NBS区域的几个保守模体：kinase2区的ILDD、kinase3的（ⅰ）ESKILVTTRSK，（ⅱ）KGSPLAARTVGG，（ⅲ）RRCFAYCS及EGF。RCCN NBS区与Cre3 NBS区的核苷酸和氨基酸的同源性分别为96.4﹪和94﹪。从氨基酸序列的274位到548位为LRR保守区，呈现不规则的aXXLXXLXXL（其中a代表I，V，L，F或M）重复，其中亮氨酸的含量为15.6﹪。该区域与Cre3的LRR区的核苷酸和氨基酸同源性分别为80.8﹪和74﹪。推测该序列可能为一个抗禾谷孢囊线虫的新基因。 本文对抗禾谷孢囊线虫基因的克隆研究，为进一步克隆基因全序列，探索其结构与功能，和研究该基因表达与调控提供了关键信息。同时也为通过基因工程途径将抗性基因向优良小麦品种高效、定向转移，最终培育出小麦抗禾谷孢囊线虫新品种奠定了基础。 Cereal cyst nematode (CCN) is a damaging pathogen of broad acre cereal crops in Australia, Europe, North America, India and China. It affects wheat, barley, oat and triticale and causes yield loss of up to 80%. At present, Transferring resistance genes against CCN into wheat cultivars and breeding varieties are considered one of the most effective methods for controlling the CCN. However, there are very limited reports concerning the cloning studies of resistance genes against the cereal cyst nematode. According to the sequence of Rccn4 which had high similarity to the nucleotide binding site (NBS) coding region of cereal cyst nematode resistance gene, Cre3， We designed three 3’ nested primers. Using single oligonucleotide nested PCR (SON-PCR) we successfully amplified one band, Rccn-L, of 1264bp from E-10 which is the wheat-Ae.variabilis translocation line containing the cereal cyst nematode resistance gene of Ae.variabilis. We found that this band of interesting is the 3’ flanking sequence of 1209bp in size of Rccn4. The coding region was 1026bp, which contained an incomplete open reading frame and a terminator codon, without initiation codon and intron, encoding a peptide of 342 amino acid residues, and shared 86﹪nucleotide sequence identity with Cre3. This peptide had a conserved LRR domain, containing the imperfect repeats,XXLXXLXXL, which contains 17﹪ leucine residues and shares, respectively, 89﹪ nucleotide sequence and 78﹪ amino acid sequence identity with the LRR sequence of Cre3 locus. This research firstly used SON-PCR in the research of plant genome successfully, which indicated that SON-PCR is another method of cloning plant gene. At the same time, According to the conversed motif of NBS and LRR region of cereal cyst nematode resistance gene Cre3 from wild wheat (Triticum tauschlii L.) and the known NBS-LRR group resistance genes, we designed two pairs of specific primers for NBS and LRR region respectively. One band of approximately 530bp was amplified using the specific primers for conversed NBS region and one band of approximately 1200bp was amplified with the specific primers for conversed LRR region. After sequencing, we found that these two sequences included 32bp common nucleotide sequence and have 1675 bp in total, which was registered as RCCN in the Genbank. RCCN contained a NBS-LRR domain and an incomplete open reading frame without initiation codon, terminator codon and inxon. Its exon encodes a peptide of 557 amino acid residues. The molecular weight of the protein from the amino acid was 63.537 KDa. The amino acid sequence of RCCN contained conserved motif: ILDD, ESKILVTTRSK, KGSPLAARTVGG, RRCFAYCS, EGF，LRR. RCCN shares 87.8﹪ nucleotide sequence and 77﹪ amino acid sequence identity with cereal cyst nematode gene Cre3. It might be a novel cereal cyst nematode resistance gene. These research results of cloning the resistance genes against cereal cyst nematode bring a great promise for transferring resistance genes into wheat cultivars and breeding new wheat varieties against cereal cyst nematode by gene engineering. And these results also lay the hard foundation for the expressing researches of these genes.

小麦胚乳蛋白组分和Glu-B3位点基因核心编码区差异与小麦品质关系的研究

小麦加工品质改良已成为我国小麦育种的主要目标之一。特别是我国加入WTO以后，对小麦产品的质量提出了更高的要求，小麦品质改良的任务将更加艰巨和重要，小麦胚乳蛋白是影响小麦加工品质性状的重要因素。因此，深入了解小麦胚乳蛋白对加工品质性状的影响及其分子基础，为品质改良提供理论依据和科学指导，对加速我国小麦品质育种和优质小麦生产具有重要意义。本研究选用在麦谷蛋白5个基因位点(Glu-A1、Glu-B1、Glu-D1、Glu-B3和Glu-D3)上均含不同等位基因的小麦品种99G45和京771及Pm97034和京771杂交F9代共164个麦谷蛋白纯合系，及228个中国推广普通小麦品种和高代育成品系为试材，研究了麦谷蛋白Glu-1和Glu-3位点基因等位变异对籽粒蛋白、湿面筋含量、Zeleny沉降值和SDS沉降值间的关系；本研究还利用小麦A、B和D基因组中低分子量麦谷蛋白亚基（LMW-GS）基因特异引物，通过PCR方法克隆了1个Glu-A3位点和3个Glu-B3位点LMW-GS基因片段，在此基础上分析了不同等位基因对品质造成差异的分子基础；另外，本研究对中国近年推广的部分品种和育成的高代品系资源的多样性进行了分析。现将主要研究结果简述如下： 1. 对来自三个麦区的148份材料的醇溶蛋白组成进行了分析，结果表明，各麦区醇溶蛋白模式具有较大差异。在ω区,A7、B、E、F、G、J、P、Q、S和U仅存在于西南秋播麦区；A3、M、N、R、W和X仅存在于黄淮特种麦区；K仅存在于北方冬麦区；A6是北方冬麦区出现频率最高的带型模式，而西南秋播麦区中D出现的频率最高。ω-区的E、H和M几种模式是以前国内外未曾报道的。且初步确定，这些模式对品质性状具有正效应。至于γ区,A、B、D、E和F在各区均有出现，其中B和E在各区出现的频率都很高，在26.1-39.6％之间。相反，H 仅出现在黄淮特种麦区，J仅限于西南秋播麦区。对于β-区醇溶蛋白，B型模式在所有区中都相当高，而模式A仅存在于第三区.对于α-区，模式A在Ⅲ区而模式D在Ⅱ区出现的频率很高。1BL.1RS易位系在中国小麦品种中出现频率高达41.2％，在I, II和Ⅲ麦区的出现频率分别为 45.5、43.5和35.2%。各生态区模式的差异可能是品种适应不同生态条件和人为选择的结果，但这有待进一步证明。由于醇溶蛋白位点（Gli-1）与LMW-GS位点（Glu-3）紧密连锁，本结果可为下面确定普通小麦LMW-GS等位基因变异所用。 2. 利用Gli-1与Glu-3的紧密连锁，以228个小麦品种/系为材料，首次对中国小麦品种麦谷蛋白亚基的6个位点进行综合分析，研究小麦籽粒蛋白与品质性状间的关系，结果表明6个高分子量（HMW）和低分子量（LMW）麦谷蛋白位点对蛋白质含量的效应大小为，Glu-D1>Glu-B3>Glu-A1=Glu-B1> Glu-A3=Glu-D3；对GMP含量的效应大小为, Glu-A3>Glu-B3>Glu-D1> Glu-B1>Glu-A1>Glu-D3；对湿面筋含量的效应大小为, Glu-B1>Glu-B3= Glu-D3>Glu-A3>Glu-A1>Glu-D1；对Zeleny沉降值的效应大小为, Glu-A1> Glu-B3>Glu-D3>Glu-D1>Glu-B1>Glu-A3；对SDS沉降值的效应大小为, Glu-B3>Glu-A1=Glu-D1=Glu-A3>Glu-D3>Glu-B1。对蛋白含量而言，各位点的最佳组合方式为1、17+18、5+10、Glu-A3e、Glu-B3g、Glu-D3b；对湿面筋含量而言，各位点的最佳组合方式为1、6+8、5+10、Glu-A3d、Glu-B3c、Glu-D3b；对Zeleny沉降值而言，各位点的最佳组合方式为N、17+18、5+10、Glu-A3d、Glu-B3d、Glu-D3b；对SDS沉降值而言，各位点的最佳组合方式为1、7+8、2.2+12、Glu-A3b、Glu-B3g、Glu-D3b。另外，分析了稀有亚基对5+12与2.2+12与品质性状的关系，认为5+12对品质有负效应，2.2+12对品质有正效应。在品质育种时，应对优异组合或优异亚基加以利用。 3. 首次利用重组自交系（RILs）为材料，研究麦谷蛋白亚基表达量与品质性状的关系，通过对重组自交系中各HMW-GS表达量的分析，认为，就单个亚基的表达量而言，7亚基最高；其次为2亚基、5亚基、12亚基和10亚基；亚基9和1的表达量最小；N亚基不表达。对成对出现的亚基对而言，x型和y型亚基的总表达量2+12>5+10>7+9>17+18。就单个亚基与品质性状的关系而言，仅有10亚基的表达量与蛋白含量的相关性达5%的显著水平，2亚基的表达量与湿面筋含量呈负相关，显著水平也达5%，其余单个亚基对品质性状均无显著影响；就x型/y型亚基的比例来看，2/12和5/10对湿面筋含量都有显著的负效应；对某一位点等位基因控制的亚基表达总量来看，2+12对SDS沉降值有显著负效应。另外，本研究得出：2＋12的亚基对的负效应主要体现在2亚基上，且在同一位点上，x型亚基的表达量大于y型。所以推导稀有亚基组合2+10很可能也是劣质亚基。 4. 以 Glu-A1、Glu-B1、Glu-D1、Glu-B3和Glu-D3作为5个因素对99G45/京771和Pm97034/京771杂交后代的蛋白质含量和SDS沉降值进行多因素方差分析。结果表明，Glu-A1和Glu-D3对蛋白含量的加性效应达5％显著水平；Glu-D1 * Glu-D3对蛋白质含量的互作效应也达5%显著水平；其余位点的加性和互作效应对蛋白质含量的影响均不显著。对SDS 沉降值而言，Glu-D1的加性效应最大,贡献率为4.2 % ,达1 %显著水平,其次是Glu-B1位点,贡献率为3.3% ,达5%显著水平。其余位点对SDS 沉降值的加性和互作效应均未达5%显著水平。总体而言, 各位点对蛋白含量的效应大小为Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3；对SDS沉降值的效应大小为Glu-D1>Glu-B1> Glu-D3>Glu-A1> Glu-B3。Glu-D1和Glu-D3位点上等位基因变异对蛋白含量有显著或极显著影响，含Glu-D1d和Glu-D3 GD、Glu-D3 JD基因的株系分别比含Glu-D1a和Glu-D3 PD基因的株系有较高的蛋白含量；在该遗传背景下，麦谷蛋白各基因位点对蛋白含量的效应大小依次排列为：Glu-A1位点1>N；Glu-B1位点7+9>17+18>14+15；Glu-D1位点5+10>2+12；Glu-B3位点GB>JB>PB；Glu-D3位点GB>JB>PB。对SDS沉降值的效应大小依次排列为：Glu-A1位点1>N；Glu-B1位点7+9=17+18>14+15；Glu-D1位点5+10>2+12；Glu-B3位点GB>JB>PB；Glu-D3位点GB>JB>PB。所以，对蛋白含量和SDS沉降值均较好的组合为1，7+9，5+10，GB，GD。 5. 因为GB和PB对品质的效应有显著差异，选取LMW-GS位点特异扩增引物对京771、99G45和Pm97034的Glu-B3位点进行扩增，结果得到三个不一样的扩增片段（Genebank号为DQ539657－DQ539659），得到的基因片段与Genebank中已报道的同类序列高度同源。通过克隆片段组成的分析，发现对Pm97034的序列较京771和99G45段少一个7氨基酸的重复单元，这可能是它较另外两个片段对面筋强度影响小的主要原因；另外，在99G45的序列中，124位处出现L（亮氨酸）代替P（脯氨酸），158位处出现了T（苏氨酸）代换M(蛋氨酸)，这可能是99G45Glu-B3位点序列对SDS沉降值的效应显著优于Pm97034的原因。 6．通过对RILs各位点同普通小麦品种（系）各位点与品质关系的比较，发现对SDS沉降值的效应，各位点在不同研究材料中是不同的，普通小麦中：Glu-B3>Glu-A1=Glu-D1=Glu-A3>Glu-D3>Glu-B1，RILs中：Glu-D1>Glu-B1> Glu-D3>Glu-A1> Glu-B3。利用重组自交系材料（完全排除了1BL/1RS易位干扰）所得到的结果与Gupta and MacRitchie (1994)所得结论一致。进一步证实了1BL/1RS易位对小麦品质的重要影响。对蛋白含量而言，普通小麦品种（系）中，Glu-D1>Glu-B3>Glu-A1=Glu-B1> Glu-A3=Glu-D3，RILs中，Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3，和对SDS沉降值的效应一样，推断在非1BL/1RS易位的情况下，各位点对其效应应为Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3。 对同一位点的等位基因而言，普通小麦和重组自交系中Glu-A1和Glu-D1上的等位基因对品质性状的贡献是一致的，但Glu-B1上的等位基因对SDS沉降值的贡献发生了变化，普通小麦中17+18>7+9，RILs中7+9>17+18，这可能也是1BL/1RS造成的。 Baking quality improved is one of the main object of wheat bread in China. The overall objective of the present studies was to increase the understanding about protein quality in wheat, i.e. to make it possible to improve the production of wheat with desired quality for different end-uses. With the analysis of gluten protein in RILs, 99G45/Jing 771 and Pm97034/Jing, and 228 wheat cultivars or lines in China, the correlations between glutenin compositions and protein content, glutenin macropolymer(GMP), wet gluten content, Zeleny sedimentation value and SDS sedimentation value contentand breadmaking quality were studied. Also a rapid and efficient detection method of geneticpolymorphism at Glu-B3 loci in wheat was established using polymerase chain reaction(PCR).The results obtained were as follows: 1. Cultivated Chinese wheat germplasm has been a valuable genetic resource in international plant breeding. Patterns of gliadin among cultivated Chinese accessions are unknown, despite the proven value and potential novelty. The objective of this work was to analyse the diversity within improved Chinese wheat germplasm. The electrophoretic banding patterns of gliadin in common wheat cultivars and advanced lines were determined by acid-polyacrylamide gel electrophoresis. For 148 leading commercial cultivars and promising advanced lines used in our study, 48 patterns were identified, 29 corresponding to ω-gliadin, 9 to γ-gliadin, 5 to β-gliadin and 5 to α-gliadin. The most frequent patterns were A6 in ω; B in γ; B in β and A in the region of α. 116 band types appeared in the148 samples: 94 accessions had unique gliadin types, and 22 gliadin types while not unique were found in 54 accessions. The gliadin patterns of Chinese wheat cultivars and lines greatly differed from the patterns of wheat lines from other countries. Three patterns, E, J, H, M, N and O in the ω-zone had not previously been reported. Three wheat zones，the Northern Winter Wheat Region, the Yellow and Huai Valley River valleys Winter Wheat Region and the Southwestern Winter Wheat Region，in China showed different frequencies in their gliadin patterns. This information can be used to monitor genetic diversity with Chinese wheat germplasm. 2. To analyse the relationship between the loci and characteristics quality, we utilized the 228 cultivars/lines. The results showed that : For protein content, Glu-D1 >Glu-B3>Glu-A1=Glu-B1>Glu-A3=Glu-D3. For GMP content, Glu-A3>Glu-B3 >Glu-D1>Glu-B1>Glu-A1>Glu-D3. For wet gluten content, Glu-B1>Glu-B3= Glu-D3>Glu-A3>Glu-A1>Glu-D1. For Zeleny sedimentation value, Glu-A1>Glu-B3> Glu-D3>Glu-D1>Glu-B1>Glu-A3, For SDS sedimentation value, Glu-B3>Glu-A1= Glu-D1= lu-A3>Glu-D3>Glu-B1。For protein content, the best combination of 6 loci is (1,17+18,5+10,Glu-A3e, Glu-B3g,Glu-D3b). For wet gluten content, the best combination of 6 loci is (1,6+8,5+10,Glu-A3d,Glu-B3c,Glu-D3b). For Zeleny sedimentation value, the best combination of 6 loci is (N,17+18,5+10,Glu-A3d, Glu-B3d, Glu-D3b). For SDS sedimentation value, the best combination of 6 loci is(7+8,2.2+12,Glu-A3b, Glu-B3g,Glu-D3b)。Additional, we analysed the relationship between the subunits 5+12 and 2.2+12, think that 5+12 was negative for quality, 2.2+12 is postive for quality. It should be effective utilized. 3. It’s the first time to utilize RILs to study the relationship between subunits expression quantity and characteristics quality. The results showed that: For single subunit, the expression quantity of 7 is the highest. Then the 2, 5, 12 and 10. The expression of subunit 9 and 1 is the lowest. Subunit N is not expressed. For subunits, the expression quantity of x type and y type are 2+12>5+10>7+9>17+18. The significant relation of 5% only showed between the expression quantity of subunit 10 and protein content. The relationship between expression quantity of others and characteristic quality was not significant. For x type/ytype, 2/12 and 5/10 is negative relation insignificant level. For the subunit(s) in a loci, Only 2+12 effect SDS sedimentation value negative in significant level. 4. With RILs 99G45/Jing 771 and Pm97034/Jing 771, we found that: The effective of Glu-A1, Glu-D3 and Glu-D1 * Glu-D3 for protein content is significant at 5% level. The effect of other loci for protein wre not significant. For SDS sedimentation value, the effect of Glu-D1is the highest, which contribution is 4.2 % .Then the Glu-B1, contribution is 3.3%. The effect of other loci for SDS sedimentationvalue were not significant. In total, for protein content: Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3; for SDS sedimentationvalue: Glu-D1>Glu-B1> Glu-D3>Glu-A1>Glu-B3. The effect of alleles in Glu-D1 and Glu-D3 loci are significant at 1% or 5%. In Glu-A1, 1>N; Glu-B1, 7+9>17+18>14+15; Glu-D, 5+10>2+12; Glu-B3, GB>JB>PB; Glu-D3, GB>JB>PB. For SDS sedimentation, Glu-A1, 1>N; Glu-B1, 7+9=17+18>14+15; Glu-D1, 5+10>2+12; Glu-B3, GB>JB>PB; Glu-D3, GB>JB>PB. The best combinations for SDS sedimentation value is 1，7+9，5+10，GB，GD. 5. Because of the difference of GB and PB for SDS sedimentation value, we selected the specific primer for LMW-GS loci to amplified the Glu-B3 of Jing771, 99G45and Pm97034. We got 3 amplify fragment (Gene Bank accession number are DQ539657－DQ539659）. We found that the fragment of Pm97034 were deleted a repetitive 7 amino acid domain, which is perhaps the reason effect the gluten strength. Furthermore, in the position 124 of sequence 99G45, L has been replaced with P. Position 158, T replaced M, which may be the reason why the Glu-B3 locus of 99G45 is prefer to Pm97034 when refer to SDS sedimentation value. 6. Comparing the results of RILs and common wheat, we found that perhaps just the1BL/1RS made the difference of loci in different accession.

小麦抗禾谷孢囊线虫（ Heterodera avenae）相关基因的研究

禾谷孢囊线虫严重影响禾谷类作物的产量，在小麦中由禾谷孢囊线虫引起的产量损失可达30-100%。尤其在澳大利亚、欧洲、印度和中东危害严重，目前禾谷孢囊线虫已成为危害我国作物的主要病源。控制禾谷孢囊线虫的方法主要有：作物轮作、杀线虫剂、寄主抗性等等，其中基因工程方法培育抗线虫小麦品种被认为是最经济有效的方法。分离抗禾谷类孢囊线虫基因对揭示抗性基因结构与功能及其表达调控具有重要意义。 尽管小麦是重要的粮食作物，在小麦中已发现的抗禾谷孢囊线虫的基因很少，而比其近缘属如节节麦、易变山羊草、偏凸山羊草中含有丰富的抗源。目前已鉴定出禾谷孢囊线虫抗性位点Cre，并发现了9个禾谷孢囊线虫抗性基因(Cre1,2, 3, 4, 5, 6, 7, 8, and R) ，其中只有Cre1和Cre8直接从普通小麦中获得。从节节麦中获得的Cre3基因能最有效的控制线虫数量，其次是Cre1和Cre8。这些基因的克隆对于了解禾谷孢囊线虫抗性机制及进一步的育种应用都是非常关键的。然而，目前为止仅有Cre3基因通过图位克隆的方法从节节麦中被分离得到。该基因已被克隆得到的多数线虫抗性基因一样均属于核苷酸结合位点区（NBS）－亮氨酸重复序列区（LRR）基因家族。目前，已有很多抗性基因被分离，这些已知的NBS-LRR类抗性基因的保守序列为应用PCR的方法克隆新的抗性基因提供了可能。 因此本课题的目的是采用保守区同源克隆、3′RACE 和5′RACE 等方法从抗禾谷孢囊线虫小麦-易变山羊草小片段易位系E10 中克隆小麦抗禾谷孢囊线虫基因全序列，进而通过半定量PCR 和荧光定量PCR 研究该基因的表达模式。同时通过mRNA 差别显示技术和任意引物PCR（RAP-PCR）技术分离克隆植物禾谷孢囊线虫抗性基因及其相关基因，为阐明植物抗病性分子机制以及改良作物抗病性和作物育种提供基础，为通过分子标记辅助育种和基因工程方法实现高效、定向转移抗病基因到优良小麦品种奠定了重要的理论和物质基础。主要研究结果： 1． 本实验根据此前从抗禾谷孢囊线虫材料E-10 扩增得到的与来自节节麦的抗禾谷孢囊线虫Cre3 基因及其他的NBS-LRR 类抗性基因的NBS 和LRR 保守区序列设计了两对特异性引物，从E10 中扩增到532bp 和1175bp 的两个目标条带，它们有一个32bp 的共同序列，连接构成总长为1675bp 的NBS-LRR 编码区（命名为RCCN）。根据RCCN设计引物，利用NBS-LRR区序列设计引物，通过5′RACE 和3′RACE 技术采用3′-Full RACE Core Set(TaKaRa)和5'-Full RACE Kit (TaKaRa)试剂盒，反转录后通过嵌套引物GSP1 和GSP2 分别进行两轮基因特异性扩增，分别将NBS_LRR 区向5′端和3′端延伸了1173bp 和449bp，并包含了起始密码子和终止密码子。根据拼接的得到的序列重新设计引物扩增进行全基因扩增的结果与上面获得的一致。拼接后得到全长2775 bp 的基因序列（记作CreZ, GenBank 号：EU327996）。CreZ 基因包括完整的开放阅读框，全长2775 bp，编码924个氨基酸。序列分析表明它与已知的禾谷孢囊线虫抗性基因Cre3的一致性很高，并且它与已经报到的NBS-LRR 类疾病抗性基因有着相同的保守结构域。推测CreZ基因可能是一个新的NBS-LRR 类禾谷孢囊线虫抗性基因，该基因的获得为通过基因工程途径培育抗禾谷孢囊线虫小麦新品种奠定了基础，并为抗禾谷孢囊线虫基因的调控表达研究提供了参考。 2． 通过半定量PCR和SYBR Green荧光定量PCR技术对CreZ基因的相对表达模式进行了研究。以α-tubulin 2作为参照，采用半定量PCR 分析CreZ 基因在不同接种时期1d, 5d, 10, 15d 的E-10的根和叶的的表达情况。在内参扩增一致的条件下，CreZ 在E-10的根部随着侵染时间的增加表达量有明显的增加，在没有侵染的E-10的根部其表达量没有明显变化，而在叶中没有检测表达，说明该基因只在抗性材料的根部表达。SYBR Green定量PCR分析接种前后E10根部基因CreZ基因的表达水平为检测CreZ基因的表达建立了一套灵敏、可靠的SYBRGreen I 荧光定量PCR 检测方法。接种禾谷孢囊线虫后E10根内CreZ基因的相对表达水平显著高于接种前。随接种时间的延长持续增加，最终CreZ基因的相对表达量达到未接种的对照植株的10.95倍。小麦禾谷孢囊线虫抗性基因CreZ的表达量与胁迫呈正相关，表明其与小麦的的禾谷孢囊线虫抗性密切相关，推测CreZ基因可能是一个新的禾谷孢囊线虫候选抗性基因。 3． 针对小麦基因组庞大、重复序列较多，禾谷孢囊线虫抗性基因及其相关基因的片断难以有效克隆的问题，通过mRNA 差别显示技术及RAP-PCR 技术分离克隆植物禾谷孢囊线虫抗性及其相关基因。试验最终得到154 条差异表达条带，将回收得到的差异条带的二次PCR 扩增产物经纯化后点到带正电的尼龙膜上，进行反向Northern 杂交筛选，最终筛选得到102 个阳性差异点。将其中81 个进行测序，并将序列提交到Genbank 中的dbEST 数据库，分别获得登录号(FE192210 -FE192265，FE193048- FE193074 )。序列比对分析发现，其中26 个序列与已知功能的基因序列同源；有28 条EST 序列在已有核酸数据库中未找到同源已知基因和EST，属新的ESTs 序列；另外27 个EST 序列与已知核酸数据库中的ESTs 具有一定相似性，但功能未知。其所得ESTs 序列补充了Genbank ESTs 数据库，为今后进一步开展抗禾谷类孢囊线虫基因研究工作打下了基础。结合本试验功能基因的相关信息，对小麦接种禾谷孢囊线虫后产生的抗性机制进行了探讨。接种禾谷孢囊线虫后植物在mRNA 水平上的应答是相当复杂的，同时植物的抗病机制是一个复杂的过程，涉及到多个代谢途径的相互作用。 The cereal cyst nematode (CCN), Heterodera avenae Woll, causes severe yieldreductions in cereal crops. The losses caused by CCN can be up to 30-100% in somewheat fields. At present, cereal cyst nematode has become the major disease sourcein China and it also damaged heavily in Australia, Europe, India and Middle East.The damage caused by CCN can be mitigated through several methods, includingcrop rotation, nematicide application, cultural practice, host resistance, and others.Of these methods, incorporating resistance genes into wheat cultivars and breedingresistant lines is considered to be the most cost-effective control measure forreducing nematode populations. Although wheat is an economically important crop around the world, far fewergenes resistant to CCN were found in wheat than were detected in its relatives, suchas Aegilops taucchi, Aegilops variabilis and Aegilops ventricosa. Cloning these genesis essential for understanding the mechanism of this resistance and for furtherapplication in breeding. Because of the huge genome and high repeat sequencescontent, the efficient methods to clone genes from cereal crops, are still lacking. A resistance locus, Cre, has been identified and 9 genes resistant to CCN (designatedCre1, 2, 3, 4, 5, 6, 7, 8, and R) have been described, in which Cre1 and Cre8 werederived directly from common wheat. The Cre3 locus, which was derived from Ae.tauschii, has the greatest impact on reducing the number of female cysts, followed byCre1 and Cre8. Cloning these genes is essential for understanding the mechanism ofthis resistance and for further application in breeding. However, to this point, only Cre3, a NBS-LRR disease resistance gene, has been obtained through mappingcloning in Ae. tauschii. The majority of nematode resistance genes cloned so far belong to a super familywhich contains highly conserved nucleotide-binding sites (NBS) and leucine-richrepeat (LRR) domains. To date, many NBS-LRR resistance genes have been isolated.The conserved sequences of these recognized NBS-LRR resistance genes provide thepossibility to isolate novel resistance genes using a PCR-based strategy. The aim of the present study was to clone the resistance gene of CCN fromWheat/Aegilops variabilis small fragment chromosome translocation line E10 whichis resistant to CCN and investigate the espression profiles of this gene withsemi-quantitative PCR and real-time PCR. Another purpose of this study is cloningthe relational resistance gene for CCN by mRNA differential display PCR andRAP-PCR. These works will offer a foundation for disease defence of crop andbreeding and directional transferring resistance gene into wheat with geneengineering. Primary results as following: 1．According to the conversed motif of NBS and LRR region of cereal cystnematode resistance gene Cre3 from wild wheat (Triticum tauschlii) and the knownNBS-LRR group resistance genes, we designed two pairs of specific primers for NBSand LRR region respectively. One band of approximately 530bp was amplified usingthe specific primers for conversed NBS region and one band of approximately 1175bpwas amplified with the specific primers for conversed LRR region. After sequencing,we found that these two sequences included 32bp common nucleotide having 1675bpin total, which was registered as RCCN in the Genbank. Based on the conservedregions of known resistance genes, a NBS-LRR type CCN resistance gene analog wasisolated from the CCN resistant line E-10 of the wheat near isogenic lines (NILs), by5′RACE and 3′ RACE.designated as CreZ (GenBank accession number: EU327996) .It contained a comlete ORF of 2775 bp and encoded 924 amino acids. Sequencecomparison indicated that it shared 92% nucleotide and 87% amino acid identitieswith those of the known CCN-resistance gene Cre3 and it had the same characteristic of the conserved motifs as other established NBS-LRR disease resistance genes. 2． Usingα-tubulin 2 as exoteric reference, semi-quantitative PCR and real-timePCR analysis were conducted. The expression profiling of CreZ indicated that it wasspecifically expressed in the roots of resistant plants and its relative expression levelincreased sharply when the plants were inoculated with cereal cyst nematodes. therelative expression level of the 15days-infected E10 is the 10.95 times as that ofuninfected E10,ultimately. It was inferred that the CreZ gene be a novel potentialresistance gene to CCN. 3．We cloned the relational resistance gene for CCN by mRNA differentialdisplay PCR and arbitrarily primed PCR fingerprinting of RNA from wheat whichpossess huge and high repeat sequence content genomes. Total 154 differentialexpression bands were separated and second amplified by PCR. The products werenylon membrane. The 102 positive clones were filtrated by reverse northern dot blotand 81 of those were sent to sequence. The EST sequences were submitted toGenbank (Genbank accession: FE192210 - FE192265, FE193048 - FE193074). Thesequences alignment analysis indicated 26 of them were identical with known genes;28 were not found identical sequence in nucleic acid database; another 27 ests wereidentical with some known ests, but their functions were not clear. These ESTsenriched Genbank ESTs database and offered foundation for further research ofresistance gene of CCN.

中国青藏高原青稞抗穗发芽资源评价与α-淀粉酶基因的克隆及表达

穗发芽（PHS，preharvest sprouting）是影响禾本科作物生产的重要的灾害之一。收获时期如遇潮湿天气容易导致穗发芽发生。发生穗发芽的种子内部水解酶（主要是α-淀粉酶）活性急剧升高，胚乳贮藏物质开始降解，造成作物产量和品质严重降低。因此，选育低穗发芽风险的品种是当前作物育种工作中面临的重要任务。 青稞(Hordeum vulgare ssp. vulgare)主要分布于青藏高原，自古以来就是青藏高原人民的主要粮食。近年来，由于青稞丰富的营养成分和特有的保健品质、在燃料工业中的潜力以及在啤酒酿造工业中的利用前景，在发达国家日趋受到重视，掀起综合研究利用的热潮。我国拥有占全世界2/3 以上的青稞资源，具有发展青稞产业的得天独厚的条件。然而，由于青稞收获期间恰逢青藏高原雨季来临，常有穗发芽灾害发生，使青稞生产损失巨大。目前对青稞穗发芽研究很少，适用于育种的穗发芽抗性材料相对缺乏，不能很好的满足青稞穗发芽抗性育种的需要。本研究以青藏高原青稞为材料，对其穗发芽抗性的评价指标和体系进行构建，同时筛选青稞抗穗发芽品种并对其抗性进行评价，还利用分子生物学手段对青稞穗发芽抗性的分子机理进行了初步探讨。主要研究结果如下： 1. 本试验以来自于我国青藏高原地区的青稞为材料，对休眠性测定的温度范围进行探讨，并对各种穗发芽抗性测定方法的对青稞的适用性进行评测。通过探讨温度对13 个不同基因型的青稞籽粒发芽和休眠性表达的影响，对筛选青稞抗穗发芽资源的温度条件进行探索，并初步分析了其休眠性表达的机理。在10，15，20，25，30℃的黑暗条件下，选用新收获的13 个青稞品种为材料进行籽粒发芽实验，以发芽指数（GI）评价其休眠性。结果发现，不同品种对温度敏感性不同，其中温度不敏感品种，在各温度条件下均表现很低的休眠性；而温度敏感品种，其休眠性表达受低温抑制，受高温诱导。15℃至25℃是进行青稞休眠性鉴定的较适宜的温度范围。通过对供试材料发芽后的α-淀粉酶活性，发现温度对青稞种子的休眠性表达的影响至少在一定程度上表现在对α-淀粉酶活性的调控上。随后，对分别在马尔康和成都进行种植的34 份青稞穗发芽指数（SI），穗发芽率（SR），籽粒发芽指数（GI）和α-淀粉酶活性（AA）进行了测定和分析，发现它们均受基因型×栽培地点的极显著影响，且四个参数之间具有一定相关性。GI 参数由于其变异系数较低，在不同栽培地点稳定性好，且操作简便，是较可靠和理想的穗发芽评价参数。SI 参数可作为辅助，区别籽粒休眠性相似的材料（基因型）或全面评价材料（基因型）的穗发芽抗性特征。AA 参数稳定性较差，并且检测方法复杂，因此不建议在育种及大量材料筛选和评价时使用。此外，青稞穗发芽抗性受环境影响较大，评价时应考虑到尽可能多的抗性影响因素及其在不同栽培条件下的变异。 2. 对来自青藏高原的青稞穗发芽抗性特征及其与其它农艺性状间的关系进行研究。通过测定穗发芽指数（SI）、籽粒发芽指数（GI）和α-淀粉酶活性（AA），表明113 份青稞材料的穗发芽抗性具有显著差异。SI、GI 和AA 参数的变幅分别为1.00~8.86、0.01~0.97 和0.00~2.76，其均值分别为4.72、0.63 和1.22。根据SI 参数，六个基因型，包括‘XQ9-5’，‘XQ33-9’，‘XQ37-5’，‘XQ42-9’，‘XQ45-7’和‘JCL’被鉴定为抗性品种。综合SI、GI 和AA 参数，可以发现青稞的穗发芽抗性机制包含颖壳等穗部结构的抗性和种子自身的抗性（即种子休眠性），且供试材料中未发现较强的胚休眠品种，除‘XQ45-7’外，所有品种在发芽第四天均能检测出α-淀粉酶活性。穗部结构和种子休眠的抗性机制因基因型不同而不同，在穗发芽抗性中可单独作用或共同作用。农家品种和西藏群体分别比栽培品种和四川群体的穗发芽抗性强，而在不同籽粒颜色的青稞中未发现明显差异。相关性检验发现，青稞的穗发芽抗性，主要是种子休眠性，与百粒重、开花期、成熟期、穗长、芒长和剑叶长呈显著负相关关系，与株高相关性不显著。农艺性状可以作为穗发芽抗性材料选育中的辅助指标。本试验为青稞穗发芽抗性育种研究提供了必要的理论基础和可供使用的亲本材料。 3. α-淀粉酶是由多基因家族编码的蛋白质，在植物种子萌发时高度表达，与植物种子的萌发能力密切相关。在大麦种子发芽时，高等电点α-淀粉酶的活性远大于低等电点的α-淀粉酶。为了研究不同穗发芽抗性青稞品种中编码高等电点α-淀粉酶Amy1 基因结构与抗性间的关系，我们以筛选得到的抗性品种‘XQ32-5’（TR1）、‘XQ37-5’（TR2）、‘XQ45-7’（TR3），易感品种‘97-15’（TS1）、‘9657’（TS2）以及强休眠大麦品种‘SAMSON’（SAM）为材料，对其Amy1 基因的编码区序列进行克隆和结构分析，并对它们推导的氨基酸序列进行比较。结果显示，青稞Amy1 基因具有三个外显子、两个内含子，编码区中有13 个核苷酸变异位点，均位于2、3 号外显子，2 个变异位点位于2 号外显子。SAM 和TS1 分别在2 号外显子相应位置有5 个相同的碱基(GAACT)的插入片段。相应α-淀粉酶氨基酸序列推导发现，所有核苷酸变异中有8 个导致相应氨基酸残基的改变，其余位点为同义突变。青稞Amy1 基因编码区序列品种间相似度高达99%以上，部分序列变异可能与其穗发芽抗性有关。随后，我们又通过SYBR Green 荧光定量技术对该基因在不同发芽时间（1d~7d）的相对表达水平进行了差异性检测。结果发现，7 天内不能检测到SAM 的Amy1 基因表达，5 个青稞品种间的Amy1 基因的相对表达量均随着发芽时间延长而上升，但上升方式有所不同。弱抗品种该基因表达更早，转录本增加速率更大，且在4~5 天可达到平台期。发芽7 天中，抗性品种总转录水平明显低于易感品种。本研究结果表明，青稞Amy1 基因的转录水平是与其穗发芽抗性高度相关。 我国青藏高原青稞，尤其是农家品种的穗发芽抗性具有丰富的变异，蕴藏着穗发芽抗性育种的宝贵资源。本研究为青稞穗发芽抗性育种建立了合理抗性评价体系，筛选出可供育种使用的特殊材料，阐明了农艺性状可辅助穗发芽抗性育种，同时还对穗发芽抗性与α-淀粉酶基因的结构和表达关系进行分析，为青稞穗发芽抗性资源筛选奠定了基础。 Preharvest sprouting (PHS) is a serious problem in crop production. It often takes place when encountering damp, cold conditions at harvest time and results in the decrease of grain quality and great loss of yield by triggering the synthesis of endosperm degrading enzymes (mostly the α-amylase). Therefore, PHS is regarded as an important criterion for crop breeding. In order to minimize the risk of PHS, resistant genotypes are highly required. Hulless barley (Hordeum vulgare ssp. vulgare) is the staple food crop in Qinghai-Tibetan Plateau from of old, where is one of the origin and genetic diversity centers of hulless barley. Recently, interest in hulless barley has been sparked throughout the world due to the demonstrations of its great potential in health food industry and fuel alcohol production. Indeed, hulless barley can also be utilized to produce good quality malt if the appropriate malting conditions are used. In China, overcast and rainy conditions often occur at maturity of hulless barley and cause an adverse on its production and application. PHS resistant genotypes, therefore, are highly required for the hulless barley breeding programs. However, few investigations have been made so far on this issue. The objectives of this study were: 1) to assessment of methods used in testing preharvest sprouting resistance in hulless barley; 2) to evaluate the variability and characteristics of PHS resistance of hulless barley from Qinghai-Tibet Plateau in China; 3) to select potential parents for PHS resistance breeding; 4) to primarily study on the molecular mechanism of PHS resistance of hulless barley. Our results are as followed: 1. We investigated the temperature effects on seed germination and seed dormancy expression of hulless barley, discussed appropriate temperature range for screening of PHS resistant varieties, and analyzed the mechanism of seed dormancy expression of hulless barley. The dormancy level of 13 hulless barley were evaluated by GI (germination index) values calculating by seed germination tests at temperature of 10，15，20，25，30℃ in darkness. There were great differences in temperature sensitivity among these accessions. The insensitive accessions showed low dormancy at any temperature while the dormancy expression of sensitive accessions could be restrained by low temperature and induced by high temperature. The temperature range of 15℃ to 25℃ was workable for estimating of dormancy level of hulless barley according to our data. Analysis of α-amylase activity showed that the temperature effects on seed germination and the expression of seed dormancy be achieved probable via regulating of α-amylase activity. Furthermore, we evaluated the differences in sprouting index (SI), sprouting rate (SR), germination index (GI) and α-amylase activity (AA) between Maerkang and Chengdu among 34 accessions of hulless barley from Qinghai-Tibetan Plateau in China. These PHS sprouting parameters were significantly affected by accession×location, and they had correlation between each other. GI was the most reliable parameter because of its low CV value, good repeatability and simple operation. SI could assist in differentiating between accessions of similar dormancy or overall evaluation of the resistance. AA was bad in repeatability and had relatively complex testing method, therefore, not appropriate for breeding and evaluation and screening of PHS resistant materials. Besides, since PHS resistance of hulless barley was greatly influenced by its growth environment, possibly much influencing factors and variations between cultivated conditions should be considered. 2. In this study, large variation was found among 113 genotypes of hulless barley (Hordeum vulgare ssp.vulgare) from Qinghai-Tibetan Plateau in China, based on the sprouting index (SI), germination index (GI) and α-amylase activity (AA) which derived from sprouting test of intact spikes, germination test of threshed seeds and determination of α-amylase activity, respectively. The range of SI, GI and AA was 1.00~8.86, 0.01~0.97 and 0.00~2.76，the mean was 4.72, 0.63 and 1.22 espectively. Six resistant genotypes, including ‘XQ9-5’, ‘XQ33-9’, ‘XQ37-5’, ‘XQ42-9’, ‘XQ45-7’ and ‘JCL’, were identified based on SI. Integrating the three parameters, it was clear that both hulls and seeds involved in PHS resistance in intact spikes of hulless barley and there was no long-existent embryo dormancy found among the test genotypes. All the genotypes, except ‘XQ45-7’, had detectable α-amylase activity on the 4th day after germination. There was PHS resistance imposed by the hull and seed per se and the two factors can act together or independent of each other. Besides, landraces or Tibet hulless barley had a wider variation and relatively more PHS resistance when compared with cultivars or Sichuan hulless barley. No significant difference was found among hulless barley of different seed colors. The correlation analysis showed PHS resistance was negatively related to hundred grain weight, days to flowering, days to maturity, spike length, awn length and flag length but not related to plant height. This study provides essential information and several donor parents for breeding of resistance to PHS. 3. Alpha-amylase isozymes are encoded by a family of multigenes. They highly express in germinating seeds and is closely related to seed germination ability. In barley germinating seeds, the activity of high pI α-amylase is much higher than low pI α-amylase. The aim of this study was to determine the relationship between preharvest sprouting resistance of hulless barley and the gene structure of Amy1 gene which encodes high pI α-amylase. The coding region and cDNA of Amy1 gene of three resistant accessions, including ‘XQ32-5’ (TR1), ‘XQ37-5’ (TR2), ‘XQ45-7’ (TR3), two susceptible accessions ‘97-15’ (TS1), ‘9657’ (TS2) and one highly dormant barley accession ‘SAMSON’ (SAM) was cloned. Analysis of their DNA sequences revealed there were three exons and two introns in Amy1 gene. Thirteen variable sites were in exon2 and exon3, 2 variable sites were in intron2. SAM and TS1 had a GAACT insert segment in the same site in intron2. Only 8 variable sites caused the change of amino acid residues. There were 99% of similarity between the tested hulless barley and some of the variable sites might be related with preharvest sprouting resistance. Then, we investigated the expression level of Amy1 gene in the 7-day germination test. Results of quantitative real-time PCR indicated that the relative expression trends of Amy1 gene were the same but had significant differences in the increase fashion between hulless barleys and no detectable expression was found in SAM. Susceptible accessions had earlier expression and faster increase and reached the maximum on day 4 ~ day 5. Besides, total transcripts level was found lower in resistant accessions than susceptible accessions. This study indicated that α-amylase activity was highly related to the transcription level of Amy1 gene which not correlated to missense mutation sites. In conclusion, hulless barley, especially the landraces from Qinghai-Tibetan Plateau in China possesses high degree of variation in PHS performance, which indicates the potential of Tibetan hulless barley as a good source for breeding of resistance to PHS. This study provides several donor parents for breeding of resistance to PHS. Our results also demonstrate that agronomic traits may be used as assistants for PHS resistance selection in hulless barley. Besides, analysis of high pI α-amylase coding gene Amy1 revealed the relative high expression of was Amy1 one of the mainly reason of different PHS resistance level in hulless barley.