BADH基因转化番茄提高耐盐性的研究

甜菜碱是植物在盐、干旱或其它胁迫下在细胞中迅速积累的一种相容性有机小分子化合物，它在细胞中的积累与植物抗盐性的提高密切相关。甜菜碱醛脱氢酶（BADH）催化甜菜碱醛转化为甜菜碱。我们将来源于耐盐植物山菠菜（Atriplx hortensis L.）的BADH基因通过农杆菌介导法导入‘百丽春’番茄(Lycopersicon esculentum L. ‘Bailichun’)中，并获得15株转化植株，PCR、Southern和Northern检测表明，其中的6株有外源BADH基因的整合，5株中BADH基因能够正常表达，但不同植株间BADH基因的表达水平和BADH酶活力有较大差异。对叶片电导率的测定表明，转基因植株比野生型的耐盐性有较大提高。T1代分析表明，检测的两个转基因株系后代遵循孟德尔分离规律，90mmol/L NaCl胁迫下种子发芽率提高了2~4倍，幼苗的苗高、根长和须根数三个指标均明显优于对照。部分T1代植株在水培条件下能够耐受180mmol/L NaCl胁迫。 植物耐盐的另一机理就是利用液泡膜上存在的转运蛋白将细胞内的有毒离子区域化。我们将已转入编码转运蛋白基因AtNHX1的番茄品种‘Moneymaker’（L. esculentum‘Moneymaker’）株系X1OEA1通过农杆菌介导法转入山菠菜BADH基因，以期获得转双基因耐盐番茄。目前已获得转基因植株，PCR结果证明部分抗性幼苗中已整合了BADH基因，其它各项分子检测正在进行中。

Winter Temperature and UV Are Tightly Linked to Genetic Changes in the p53 Tumor Suppressor Pathway in Eastern Asia

The tumor suppressor p53 is a master sensor of stress. Two human-specific polymorphisms, p53 codon 72 and MDM2 SNP309, influence the activities of p53. There is a tight association between cold winter temperature and p53 Arg72 and between low UV intensity

核糖体失活蛋白抗HIV-1作用的研究进展

核糖体失活蛋白(RIPs)抗HIV-1活性研究已有十几年的历史。RIPs类化合物代表了抗HIV/AIDS天然产物或先导化合物发展的一个重要方向。本文从介绍RIPs的酶活性及其抗HIV-1活性入手,对RIPs抗HIV-1的可能机制,从与RIPs酶活性的关系、诱导HIV-1感染细胞的凋亡及相应的信号转导、诱发活性氧的产生,以及对HIV-1整合酶的抑制作用等几个方面做了较详尽的阐述,并对RIPs的结构修饰和抗HIV-1构效关系进行了综述。对RIPs类化合物在抗病毒领域进行深入而系统地研究,能拓宽其在抗HIV/AIDS临床上的进一步应用。

草鱼野生和养殖群体间遗传变异的微卫星分析

运用微卫星标记对江苏境内草鱼(Ctenopharyngodon idella)一个野生群体(邗江群体)和两个养殖群体(淡水中心群体和无锡前洲群体)遗传多样性进行了分析.在10个座位中,每个座位检测到的等位基因数2～8个.有效等位基因数、多态信息含量、期望杂合度、平均表观杂合度均以邗江草鱼野生群体最高,分别为3.9、0.506 8、0.693 9、0.7;无锡前洲草鱼养殖群体最低,分别为2.2、0.179 6、0.523 5、0.528 6;淡水中心草鱼养殖群体各参数均介于两者之间,分别为3.5、0.290 2、0.541 8、0.542 9.以上结果表明:草鱼野生群体遗传多样性更为丰富,而草鱼养殖群体存在杂合度降低,遗传多样性下降的现象.邗江草鱼野生群体与淡水中心草鱼养殖群体和无锡前洲草鱼养殖群体间遗传分化系数分别为0.219和0.246,而两个草鱼养殖群体间遗传分化系数为0.034.这表明草鱼野生群体与草鱼养殖群体间分化严重,而草鱼养殖群体间分化微弱.各座位分化程度的χ2检验结果表明,10个座位中有GM18、MFW1-1、MFW1-2三个座位群体间分化达到极显著水平,GM03-2、MFW5两个座位群体间分化差异显著,其他座位分化不显著.针对每个座位对各群体进行Hardy-Weinberg平衡检验发现:由于草鱼养殖群体在GM03-1、GM03-2、GM18三个位点杂合子缺失,草鱼野生群体在位点GM19杂合子过剩而严重偏离平衡.实验表明:近交容易引起草鱼遗传多样性下降,纯合速度加快.

Amolops bellulus: A new species of stream-breeding frog from western Yunnan, China (Anura : Ranidae)

We describe a new species of stream-breeding frog of the genus Amolops, Amolops bellulus, from the mountainous region of Lushui County, Yunnan Province, China, near the boundary between Yunnan and Myanmar. This species differs from all its congeners in a combination of morphological characteristics including the absence of a circummarginal groove at the tip of first finger, lack of a supratympanic fold, a white band along the upper jaw extending to shoulder, a black band starting from tip of snout along upper loreal region and extending to anterior flank of body, absence of a vocal sac, tympanum distinct and feebly concave, and the presence of vomerine teeth.

椭圆背角无齿蚌对重金属元素的积累作用

检测了滇池水饲养 1a的椭圆背角无齿蚌 (Anodontawoodianaelliptica)体内重金属等元素含量 ,结果显示椭圆背角无齿蚌体内锌含量为 7.0 8× 1 0 2 mg/kg ,铅为 3 5 .6 8mg/kg ,铜为 9.0 4mg/kg ,铁为 4 .74× 1 0 3mg/kg ,砷为 6 2 .0 9mg/kg ,磷为 4 .4 4× 1 0 4mg/kg .与滇池水中锌 0 .0 2 0 5 μg/L ,铅 0 .4 1 2 μg/L ,铜 3 .1 98μg/L相比较 ,表明椭

粘孢子虫免疫学研究进展

国家自然科学基金项目 ( 3 0 2 710 2 8); 中国科学院知识创新项目 (KSCX2-1-0 4)

萼花臂尾轮虫交配行为和受精作用研究

萼花臂尾轮虫的交配行为大致可分为 5个阶段。除雌雄性比为 1∶ 2和 1∶ 3时混交雌体的受精率为 1 0 0 %外 ,其余性比下混交雌体的受精率皆无显著的差异。可受精的混交雌体百分率和具受精能力的雄体百分率皆随年龄的增大而下降。所有的混交雌体在出生后的 4 h内均易于受精 ;以后随着龄长 ( X,h)的增加 ,可受精的混交雌体百分率 ( Y,% )呈非线性下降 :Y=1 66.6386-1 7.81 3X+0 .4 837X2。当龄长达 1 8h时 ,所有的混交雌体皆不易受精。雄体在出生后的 8h内 ,

PCR-DGGE Fingerprinting Analysis of Plankton Communities and Its Relationship to Lake Trophic Status

Plankton communities in eight lakes of different trophic status near Yangtze, China were characterized by using denatured gradient gel electrophoresis (DGGE). Various water quality parameters were also measured at each collection site. Following extraction of DNA from plankton communities, 16S rRNA and 18S rRNA genes were amplified with specific primers for prokaryotes and eukaryotes, respectively; DNA profiles were developed by DGGE. The plankton community of each lake had its own distinct DNA profile. The total number of bands identified at 34 sampling stations ranged from 37 to 111. Both prokaryotes and eukaryotes displayed complex fingerprints composed of a large number of bands: 16 to 59 bands were obtained with the prokaryotic primer set; 21 to 52 bands for the eukaryotic primer set. The DGGE-patterns were analyzed in relation to water quality parameters by canonical correspondence analysis (CCA). Temperature, pH, alkalinity, and the concentration of COD, TP and TN were strongly correlated with the DGGE patterns. The parameters that demonstrated a strong correlation to the DGGE fingerprints of the plankton community differed among lakes, suggesting that differences in the DGGE fingerprints were due mainly to lake trophic status. Results of the present study suggest that PCR-DGGE fingerprinting is an effective and precise method of identifying changes to plankton community composition, and therefore could be a useful ecological tool for monitoring the response of aquatic ecosystems to environmental perturbations.

Structure, organization and expression of common carp (Cyprinus carpio L.) SLP-76 gene

SLP-76 is an important member of the SLP-76 family of adapters, and it plays a key role in TCR signaling and T cell function. Partial cDNA sequence of SLP-76 of common carp (Cyprinus carpio L.) was isolated from thymus cDNA Library by the method of suppression subtractive hybridization (SSH). Subsequently, the full length cDNA of carp SLP-76 was obtained by means of 3' RACE and 5' RACE, respectively. The full Length cDNA of carp SLP-76 was 2007 bp, consisting of a T-terminal untranslated region (UTR) of 285 bp, a T-terminal. UTR of 240 bp, and an open reading frame of 1482 bp. Sequence comparison showed that the deduced amino acid sequence of carp SLP-76 had an overall similarity of 34-73% to that of other species homotogues, and it was composed of an NH2-terminal domain, a central proline-rich domain, and a C-terminal SH2 domain. Amino acid sequence analysis indicated the existence of a Gads binding site R-X-X-K, a 10-aa-long sequence which binds to the SH3 domain of LCK in vitro, and three conserved tyrosine-containing sequence in the NH2-terminal domain. Then we used PCR to obtain a genomic DNA which covers the entire coding region of carp SLP-76. In the 9.2 k-long genomic sequence, twenty one exons and twenty introns were identified. RT-PCR results showed that carp SLP-76 was expressed predominantly in hematopoietic tissues, and was upregulated in thymus tissue of four-month carp compared to one-year old carp. RT-PCR and virtual northern hybridization results showed that carp SLP-76 was also upregulated in thymus tissue of GH transgenic carp at the age of four-months. These results suggest that the expression level of SLP-76 gene may be related to thymocyte development in teleosts. (c) 2007 Published by Elsevier Ltd.

Diurnal changes of behavior and respiration of Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) in captivity

A preliminary study was carried out to investigate diurnal changes of behavior of three, one adult mate, one adult female, and one juvenile female, Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) in captivity. The respiration and behavior of the porpoises were recorded for 222 hr across 42 days. Behavioral data were recorded for eight general categories: aerial display and fast swimming, begging for fish, playing, nonsexual socializing, sexual behavior, resting, rubbing, and miscellaneous (i.e., other behaviors not included in the above categories). Each behavioral category was scored using one-zero sampling with 10-min intervals. The adult male showed shorter mean respiratory intervals at night (19:00-7:00 h), whereas the mean respiratory intervals of the females were shorter during the day (7:00-19:00 h). Begging for fish of all individuals, playing of the juvenile female, nonsexual socializing, and miscellaneous behavior of the adult female and resting of the male were observed more easily in the day, and aerial display and fast swimming of the adults and resting of the females were observed more easily at night. No significant diurnal difference was found, however, in the remaining categories of each individual. Each of the three porpoises therefore showed a distinct diurnal pattern, but none was obviously more active in the daytime than during the nighttime. Results suggest that daytime-only feeding schedules may be insufficient to meet the energetic needs of marine mammals that show a 24-hr activity cycle, and that nighttime feeding may be a worthwhile addition to husbandry routines.

Variation in stable isotope signatures of seston and a zooplanktivorous fish in a eutrophic Chinese lake

Temporal and spatial changes in delta(13)C and delta(15)N of seston (mainly phytoplankton) and isotopic relationship between seston and the lake anchovy (Coilia ectenes) were studied in the large eutrophic freshwater Lake Chaohu in China. Much of the spatial and temporal variation in delta(13)C of lake anchovies was explained by variation in seston, indicating a strong link between pelagic primary production and higher order consumers. Because the lake is shallow, there were no significant differences in delta(13)C and delta(15)N of seston between surface and overlying waters. Spatially, the relatively high delta(13)C and delta(15)N of seston in the western part of the lake might be due to high levels of anthropogenically derived N and C introduced from the surrounding cities through sewage drainage systems. The trophic position of the lake anchovy in the food web of Lake Chaohu was estimated to be 2.9-4.1 (3.5 +/- 0.4), which agrees well with the previous stomach content analysis suggesting that the lake anchovy fed both on zooplankton and small planktivorous fishes.