Avian comparative genomics: reciprocal chromosome painting between domestic chicken (Gallus gallus) and the stone curlew (Burhinus oedicnemus, Charadriiformes) - An atypical species with low diploid number

The chicken is the most extensively studied species in birds and thus constitutes an ideal reference for comparative genomics in birds. Comparative cytogenetic studies indicate that the chicken has retained many chromosome characters of the ancestral avia

Defining the orientation of the tandem fusions that occurred during the evolution of Indian muntjac chromosomes by BAC mapping

The Indian muntjac (Muntiacus muntjak vaginalis) has a karyotype of 2n=6 in the female and 7 in the male, the karyotypic evolution of which through extensive tandem fusions and several centric fusions has been well-documented by recent molecular cytogenetic studies. In an attempt to define the fusion orientations of conserved chromosomal segments and the molecular mechanisms underlying the tandem fusions, we have constructed a highly redundant (more than six times of whole genome coverage) bacterial artificial chromosome (BAC) library of Indian muntjac. The BAC library contains 124,800 clones with no chromosome bias and has an average insert DNA size of 120 kb. A total of 223 clones have been mapped by fluorescent in situ hybridization onto the chromosomes of both Indian muntjac and Chinese muntjac and a high-resolution comparative map has been established. Our mapping results demonstrate that all tandem fusions that occurred during the evolution of Indian muntjac karyotype from the acrocentric 2n=70 hypothetical ancestral karyotype are centromere-telomere (head-tail) fusions.

竹叶青蛇毒丝氨酸蛋白酶的分子克隆和序列比较

利用逆转录酶与聚合酶链反应相结合的 RT-PCR 法, 扩增出5个竹叶青(Trimeresurus stejnegeri)蛇毒丝氨酸蛋白酶的 cDNAs; 将扩增的 cDNA 片段克隆入 pGEM-T 载体中, 筛选得到它们的基因, 分别命名为TSSP-1、TSSP-2、TSSP-3、TSSP-4 和 TSSP-5. 经末端终止法测定核苷酸序列, 推导出5个丝氨酸蛋白酶的全序列; 结合纯化的蛋白酶N-末端序列测定结果, 推导 TSSP 2、3和4分别编码凝血酶样酶 stejnobin、纤溶酶 stejnefibrase 1和2. 5个丝氨酸蛋白酶分别含有1～6个N-型糖基结合位点, 表明它们的计算分子量与纯化蛋白表观分子量之间的差异是由糖含量的不同造成, 而其氨基酸序列相似度在60%-90%, TSSP-1 和-2编码的成熟蛋白酶山236个氨基酸残基组成, TSSP-3, -4 和 -5的则山234个氨基酸残基组成, TSSP-1编码的蛋白酶在组成丝氨酸蛋白酶三联体催化活性中心产生了 His~(41)-Arg~(41)的在然突变, 这与其他自然界发现的丝氨酸蛋白酶明显不同。

A novel proline rich bombesin-related peptide (PR-bombesin) from toad Bombina maxima

A novel bombesin-related peptide was isolated from skin secretions of Chinese red belly toad Bombina maxima. Its primary structure was established as pGlu-Lys-Lys-Pro-Pro-Arg-Pro-Pro-Gln-Trp-Ala-Val-Gly-His-Phe-Met-NH2. The amino-terminal (N-terminal) 8-residue segment comprising four prolines and three basic residues is extensively different from bombesins from other Bombina species. The peptide was thus named proline rich bombesin (PR-bombesin). PR-bumbesin was found to elicit concentration-dependent contractile effects in the rat stomach strip, with both increased potency and intrinsic activity as compared with those of [Leu(13)]bombesin. Analysis of different bombesin cDNA structures revealed that an 8 to 14- nucleotide fragment replacement in the peptide coding region (TGGGGAAT in the cDNAs of multiple bombesin forms from Bombina orientalis and CACCCCGGCCACCC in the cDNA of PR-bombesin) resulted in an unusual Pro-Pro-Arg-Pro-Pro motif in the N-terminal part of PR-bombesin. (C) 2002 Elsevier Science Inc. All rights reserved.

A NOVEL PLASMINOGEN-ACTIVATOR FROM SNAKE-VENOM - PURIFICATION, CHARACTERIZATION, AND MOLECULAR-CLONING

A novel plasminogen activator from Trimeresurus stejnegeri venom (TSV-PA) has been identified and purified to homogeneity. It is a single chain glycoprotein with an apparent molecular weight of 33,000 and an isoelectric point of pH 5.2. It specifically activates plasminogen through an enzymatic reaction. The activation of human native GIu-plasminogen by TSV-PA is due to a single cleavage of the molecule at the peptide bond Arg(561)-Val-(562). Purified TSV-PA, which catalyzes the hydrolysis of several tripeptide p-nitroanilide substrates, does not activate nor degrade prothrombin, factor X, or protein C and does not clot fibrinogen nor show fibrino(geno)lytic activity in the absence of plasminogen. The activity of TSV-PA was readily inhibited by phenylmethanesulfonyl fluoride and by p-nitrophenyl-p-guanidinobenzoate. Oligonucleotide primers designed on the basis of the N-terminal and the internal peptide sequences of TSV-PA were used for the amplification of cDNA fragments by polymerase chain reaction. This allowed the cloning of a full-length cDNA encoding TSV-PA from a cDNA library prepared from the venom glands. The deduced complete amino acid sequence of TSV-PA indicates that the mature TSV-PA protein is composed of 234 amino acids and contains a single potential N-gIycosylation site at Asn(1G1). The sequence of TSV-PA exhibits a high degree of sequence identity with other snake venom proteases: 66% with the protein C activator from Aghistrodon contortrix contortrix venom, 63% with batroxobin, and 60% with the factor V activator from Russell's viper venom. On the other hand, TSV-PA shows only 21-23% sequence similarity with the catalytic domains of u-PA and t-PA. Furthermore, TSV-PA lacks the sequence site that has been demonstrated to be responsible for the interaction of t-PA (KHRR) and u-PA (RRHR) with plasminogen activator inhibitor type 1.

Perspectives on the origin of microfilaments, microtubules, the relevant chaperonin system and cytoskeletal motors - a commentary on the spirochaete origin of flagella

The origin of cytoskeleton and the origin of relevant intracellular transportation system are big problems for understanding the emergence of eukaryotic cells. The present article summarized relevant information of evidences and molecular traces on the origin of actin, tubulin, the chaperonin system for folding them, myosins, kinesins, axonemal dyneins and cytoplasmic dyneins. On this basis the authors proposed a series of works, which should be done in the future, and indicated the ways for reaching the targets. These targets are mainly: 1) the reconstruction of evolutionary path from MreB protein of archaeal ancestor of eukaryotic cells to typical actin; 2) the finding of the MreB or MreB-related proteins in crenarchaea and using them to examine J. A. Lake's hypothesis on the origin of eukaryote from "eocytes" (crenarchaea); 3) the examinations of the existence and distribution of cytoskeleton made of MreB-related protein within coccoid archaea, especially in amoeboid archaeon Thermoplasm acidophilum; 4) using Thermoplasma as a model of archaeal ancestor of eukaryotic cells; 5) the searching for the homolog of ancestral dynein in present-day living archaea. During the writing of this article, Margulis' famous spirochaete hypothesis on the origin of flagella and cilia was unexpectedly involved and analyzed from aspects of tubulins, dyneins and spirochaetes. Actually, spirochaete cannot be reasonably assumed as the ectosymbiotic ancestor of eukaryotic flagella and cilia, since their swing depends upon large amount of bacterial flagella beneath the flexible outer wall, but not depends upon their intracellular tubules and the assumed dyneins. In this case, if they had "evolved" into cilia and lost their bacterial flagella, they would immediately become immobile! In fact, tubulin and dynein-like proteins have not been found in any spirochaete.

Frog albumin is expressed in skin and characterized as a novel potent trypsin inhibitor

A novel potent trypsin inhibitor was purified and characterized from frog Bombina maxima skin. A full-length cDNA encoding the protein was obtained from a cDNA library constructed from the skin. Sequence analysis established that the protein actually comprises three conserved albumin domains. B. maxima serum albumin was subsequently purified, and its coding cDNA was further obtained by PCR-based cloning from the frog liver. Only two amino acid variations were found in the albumin sequences from the skin and the serum. However, the skin protein is distinct from the serum protein by binding of a haem b (0.95 mol/mol protein). Different from bovine serum albumin, B. maxima albumin potently inhibited trypsin. It bound tightly with trypsin in a 1: 1 molar ratio. The equilibrium dissociation constants (K-D) obtained for the skin and the serum proteins were 1.92 x 10(-9) M and 1.55 x 10(-9) M, respectively. B. maxima albumin formed a noncovalent complex with trypsin through an exposed loop formed by a disulfide bond (Cys(53)-Cys(62)), which comprises the scissile bond Arg(58)(P-1)-His(59)(P-1'). No inhibitory effects on thrombin, chymotrypsin, elastase, and subtilisin were observed under the assay conditions. Immunohistochemical study showed that B. maxima albumin is widely distributed around the membranes of epithelial layer cells and within the stratum spongiosum of dermis in the skin, suggesting that it plays important roles in skin physiological functions, such as water economy, metabolite exchange, and osmoregulation.

Identification and molecular cloning of a novel neuromedin U analog from the skin secretions of toad Bombina maxima

Amphibian skin contains rich neuropeptides. In the present study, a novel neuromedin U (NmU) analog was isolated from skin secretions of Chinese red belly Load Bombina maxima. Being 17-amino acids long, its primary structure was established as DSSGIVGRPFFLFRPRN-NH2, in which the C-terminal 8-residue segment (FFLFRPRN) is the same as that of rat NmU, while the N-terminal part DSSGIVGRP shows a great sequence variation compared with those of NmU peptides from different resources. The peptide, named Bm-NmU-17, was found to elicit concentration-dependent contractile effects on smooth muscle of rat uterus horns. The cDNA Structure of the peptide, as obtained by a 3'-RACE strategy and subsequently cloning from a skin cDNA library, was found to contain a coding region of 438 nucleotides. The encoded precursor is composed of 145 amino acids with a single copy of Bm-NmU-17 located towards the C-terminus. The sequence of the peptide is preceded by a dibasic site (Lys-Arg) and followed by the sequence of Gly-Arg-Lys, providing the sites of cleavage and releasing of the mature peptide. (c) 2005 Elsevier B.V. All rights reserved.

饱食因子及其制备方法和其基因

本发明涉及一种饱食因子及其制备方法和其基因，属于生物医学领域。该饱食因子为从中国两栖类动物大蹼铃蟾(Bombina maxima)皮肤分泌物中分离得到的由28个氨基酸组成的一种单链多肽，分子量3229.57，等电点7.7，多肽氨基酸全序列一级结构为：Asp Met Tyr Glu Ile Lys Gln Tyr Lys The Ala HisGly Arg Pro Pro Ile Cys Ala Pro Gly Glu Gln Cys Pro Ile Trp Val-AMIDATION。制备方法是收集大蹼铃蟾皮肤分泌物，离心去除沉淀、冷冻干燥后，经凝胶过滤、离子交换柱层析、高压液相反相柱层析分离纯化后即得到。编码饱食因子的基因由1041个核苷酸组成，其中编码成熟饱食因子为第835-918位核苷酸。具有抑制进食，增强缓激肽生物效应的作用，作为制备肥胖症治疗药物，心血管系统疾病治疗药物的应用。

A novel family of antimicrobial peptides from the skin of Amolops loloensis

While conducting experiments to investigate antimicrobial peptides of amphibians living in the Yunnan-Sichuan region of southwest China, a new family of antimicrobial peptides was identified from skin secretions of the rufous-spotted torrent frog, Amolops loloensis. Members of the new peptide family named amolopins are composed of 18 amino acids with a unique sequence, for example, NILSSIVNGINRALSFFG. By BLAST search, amolopins did no show similarity to any known peptides. Among the tested microorganisms, native and synthetic peptides only showed antimicrobial activities against Staphylococcus aureus ATCC2592 and Bacillus pumilus, no effects on other microorganisms. The CD spectroscopy showed that it adopted a structure of random combined with beta-sheet in water, Tris-HCl or Tris-HCl-SDS. Several cDNAs encoding amolopins were cloned from the skin cDNA library of A. loloensis. The precursors of amolopin are composed of 62 amino acid residues including predicted signal peptides, acidic propieces, and mature antimicrobial peptides. The preproregion of amolopin precursor comprises a hydrophobic signal peptide of 22 residues followed by an 18 residue acidic propiece which terminates by a typical prohormone processing signal Lys-Arg. The preproregions of precursors are very similar to other amphibian antimicrobial peptide precursors but the mature amolopins are different from other antimicrobial peptide families. The remarkable similarity of preproregions of precursors that give rise to very different antimicrobial peptides in distantly related frog species suggests that the corresponding genes form a multigene family originating from a common ancestor. (C) 2008 Elsevier Masson SAS. All rights reserved.

无指盘臭蛙皮肤活性肽及其基因和在制药中的应用

本发明涉及一种无指盘臭蛙皮肤活性肽及及其基因和在制药中的应用，属于生物医学领域。无指盘臭蛙皮肤活性肽是无指盘臭蛙皮肤活性肽基因编码的一种单链多肽，分子量3015.63道尔顿，等电点10.3，多肽全序列一级结构为： Ala Thr Ala Leu Gly Leu Ser Ser Arg Gly Leu Leu Pro Ile Gly Phe Met Phe Lys Asp Thr Ile Arg Cys Arg Lys Tyr(ATALGLSSRGLLPIGFMFKDTIRCRKY)。编码无指盘臭蛙皮肤活性肽的基因由312个核苷酸组成，其中编码成熟无指盘臭蛙皮肤活性肽为第141-222位核苷酸。人工合成的无指盘臭蛙皮肤活性肽具有很强的抑制细菌和真菌生长的作用，可以作为制备病原微生物感染疾病的治疗药物被应用。无指盘臭蛙皮肤活性肽具有结构简单、人工合成方便、抗菌谱系广、抗菌活性强的特点。

无指盘臭蛙免疫调节肽、其基因和变异体及其在制药中的应用

本发明涉及无指盘臭蛙免疫调节肽、基因和变异体及其在制药中的应用，属生物医学技术领域。无指盘臭蛙免疫调节肽是一种环状多肽，分子量1791.12道尔顿，等电点 9.84，无指盘臭蛙免疫调节肽的全序列为：Thr Ser Arg Cys Tyr Ile Gly Tyr Arg Arg Lys Val Val Cys Ser(TSRCYIGYRRKVVCS)，其第4位的半胱氨酸和第14位的半胱氨酸形成分子内二硫键。编码的基因由307个核苷酸组成，其中编码成熟部分的为第 141-186位核苷酸。无指盘臭蛙免疫调节肽原始序列中第4个氨基酸发生替代所产生的变异体，人工合成的无指盘臭蛙免疫调节肽及其变异体具有强烈的免疫调节活性和肿瘤抑制活性，作为制备免疫调节、肿瘤治疗和化疗药物的应用。本发明还具有序列简单、合成方便等优点。

无指盘臭蛙抗微生物多肽及其基因和在制药上的应用

本发明涉及一种无指盘臭蛙抗微生物多肽及其基因和在制药上的应用，属于生物医学领域。无指盘臭蛙抗微生物多肽是无指盘臭蛙抗微生物多肽基因编码的一种单链多肽，分子量为4248.27道尔顿，等电点为11.47，多肽全序列一级结构为：Gly Leu Phe Thr Leu Ile Lys Gly Ala Ala Lys Leu Ile Gly Lys Thr Val Pro Lys Lys Gln Ala Arg Leu Gly Met Asn Leu Trp Leu Val Lys Leu Pro Thr Asn Val Lys Thr (GLFTLIKGAAKLIGKTVPKKQARLGMNLWLVKLPTNVKT)。编码无指盘臭蛙抗微生物多肽的基因由343个核苷酸组成，其中编码成熟无指盘臭蛙抗微生物多肽为第123-240位核苷酸。人工合成的无指盘臭蛙抗微生物多肽具有很强的抑制细菌和真菌生长的作用，可以作为制备病原微生物感染疾病的治疗药物被应用。本发明的无指盘臭蛙抗微生物多肽具有抗菌谱系广、抗菌活性强的特点。

无指盘臭蛙分泌肽及其基因和在制药中的应用

本发明涉及一种无指盘臭蛙分泌肽及其基因和在制药中的应用，属于生物医学领域。该活性多肽是从中国两栖类动物无指盘臭蛙基因编码的一种环状多肽，分子量1587.98道尔顿，等电点9.7，多肽全序列一级结构为： Phe Met Pro Ile Leu Ser Cys Ser Arg Phe Lys Arg Cys，其第七位半胱氨酸和第十三位半胱氨酸相成分子内二硫键。编码无指盘臭蛙分泌肽的基因由300个核苷酸组成，其中编码成熟无指盘臭蛙分泌肽为第138-177位核苷酸。人工合成的无指盘臭蛙分泌肽具有显著的抑制细菌和真菌生长的作用，可以作为制备病原微生物感染疾病的治疗药物被应用。本发明的无指盘臭蛙分泌肽具有结构简单、人工合成方便、抗菌谱系广的有益特点。

无指盘臭蛙臭蛙肽及其基因和在制药中的应用

本发明涉及一种无指盘臭蛙臭蛙肽及其基因和在制药中的应用，属于生物医学领域。无指盘臭蛙臭蛙肽是无指盘臭蛙臭蛙肽基因编码的一种单链多肽，分子量1814.11道尔顿，等电点8.08，多肽全序列一级结构为： Gly Cys Ser Arg Trp Ile Ile Gly Ile His Gly Gln Ile Cys Arg Asp。(GCSRWIIGIHGQICRD)。编码无指盘臭蛙臭蛙肽的基因由312个核苷酸组成，其中编码成熟无指盘臭蛙臭蛙肽为第141-189位核苷酸。人工合成的无指盘臭蛙臭蛙肽具有很强的抑制细菌和真菌生长的作用，可以作为制备病原微生物感染疾病的治疗药物被应用。本发明的无指盘臭蛙臭蛙肽具有结构简单、人工合成方便、抗菌谱系广、抗菌活性强的特点。