四种雉骨骼系统的比较及数值分类研究

作者通过对原鸡(Gallus gallus)、环颈雉(Phasianus colchicus)、白腹锦鸡(Chrysolophus amherstiae)和红腹锦鸡(Chrysolophus pictus)3属4种骨骼系统进行比较研究，在本文中阐明了属间及种间在骨骼系统上的区别；根据48个骨骼性状的测量值，运用数值分类学的原理和方法对3属4种22个标本进行了聚类分析；并探讨了属间的亲缘关系以及锦鸡属的种级分类问题。主要结论如下：1. 原鸡属、雉属及锦鸡属之间骨骼系统有较大的差异：原鸡属和雉属的眶后突先端与颧突先端愈合呈弓形，龙骨突发达；锦鸡属的眶后突先端与颧突先端不愈合，龙骨突不甚发达。锦鸡属与原鸡属的胫跗骨较长，而雉属较短。2. 锦鸡属两个种的骨骼形状极相似，但尺骨的长度存在着显著差异。3. 在聚类过程中，当欧氏距离为13.0012时，雉属与原鸡属先聚合，当欧氏距离为15.3379时，两者再与锦鸡属聚合。4. 根据骨骼形态及聚类分析结果，作者认为雉属与原鸡属的亲缘关系可能更接近一些，而锦鸡属可能是雉族中一个特化而孤立的属。5. 作者认为锦鸡属的白腹锦鸡和红腹锦鸡在分类地位上，作为分化较晚，亲缘关系极其密切的两个种可能更合适一些。

Molecular cloning and responsive expression to injury stimulus of a defender against cell death 1 (DAD1) gene from bay scallops Argopecten irradians

Apoptosis is an active process of cell death, which is an integral part of growth and development in multicellular organisms. The defender against cell death 1 (DAD1), the regulatory protein to inhibit the apoptosis process, was first cloned from the bay scallop Argopecten irradians by randomly sequencing a whole tissue cDNA library and rapid amplification of cDNA end (RACE). The full-length cDNA of the A. irradians DAD1 was 607 bp, consist of a 5'-terminal untranslated region (UTR) of 63 bp, a 3'-terminal UTR of 205 bp with a canonical polyadenylation signal sequence AATAAA and a poly (A) tail, and an open reading frame of 339 bp. The deduced amino acid sequence of the A. irradians DAD1 showed 75.5% identity to Araneus ventricosus, 74.5% to Drosophila melanogaster, and 73.6% to Homo sapiens, Sus scrofa, Mesocricetus auratus, Rattus norvegicus and Mus musculus. Excluding the Saccharomyces cerevisiae DAD1 homologue, all animal DAD1 including A. irradians DAD1 homologue formed a subgroup and all plant DAD1 proteins formed another subgroup in the phylogenetic analysis. The A. irradians DAD1 was expressed in all examined tissues including adductor muscle, mantle, gills, digestive gland, gonad and hemolymph, suggesting that A. irradians DAD1 is expressed in most body tissues. Furthermore, the mRNA expression levels of A. irradians DAD1 gene of hemolymph were particularly high after injury, suggesting that the gene is responsive to injury stimuli.

cDNA cloning and overexpression of acidic ribosomal phosphoprotein P1 gene (RPLP1) from the Giant Panda

RPLP1 is one of acidic ribosomal phosphoproteins encoded by RPLP1 gene, which plays an important role in the elongation step of protein synthesis. The cDNA of RPLP1 was cloned successfully for the first time from the Giant Panda (Ailuropoda melanoleuca) using RT-PCR technology, which was also sequenced, analyzed preliminarily and expressed in E. coli. The cDNA fragment cloned is 449bp in size, containing an open reading frame of 344bp encoding 114 amino acids. Alignment analysis indicated that the nucleotide sequence and the deduced amino acid sequence are highly conserved to other five species studied, including Homo sapiens, Mus musculus, Rattus norvegicus, Bos Taurus and Sus scrofa. The homologies for nucleotide sequences of Giant Panda PPLP1 to that of these species are 92.4%, 89.8%, 89.0%, 91.3% and 87.5%, while the homologies for amino acid sequences are 96.5%, 94.7%, 95.6%, 96.5% and 88.6%. Topology prediction showed there are three Casein kinase II phosphorylation sites and two N-myristoylation sites in the RPLP1 protein of the Giant Panda (Ailuropoda melanoleuca). The RPLP1 gene was overexpressed in E. coli and the result indicated that RPLP1 fusion with the N-terminally His-tagged form gave rise to the accumulation of an expected 18kDa polypeptide, which was in accordance with the predicted protein and could also be used to purify the protein and study its function.

THE ORIGIN AND GENETIC DIFFERENTIATION OF NATIVE BREEDS OF PIGS IN SOUTHWEST CHINA - AN APPROACH FROM MITOCHONDRIAL-DNA POLYMORPHISM

Mitochondrial DNA (mtDNA) of six breeds of native domestic pigs from Yunnan province, southwest China, and two wild boars obtained from Sichuan, China, and Vietnam was analyzed using 20 restriction endonucleases that recognize six nucleotides. Restriction maps were made by double-digestion methods and polymorphic sites were located on the map. According to their mtDNA restriction types, all the breeds were classified into six groups. Genetic distances among groups were calculated to define their phylogenetic relationships. The relationship between the Sichuan wild boar and domestic pigs is close, while the Vietnamese wild boar is relatively far from them, so the domestic pigs in southwest China are likely to have originated from a wild pig which distributed in west China. We compare our results with previous reports in literature and discuss the relationship among Chinese pigs, Japanese pigs, and European pigs. The mtDNA cleavage pattern of the Mingguang pig digested by EcoRV was identical to that of Duroc; mutations at the EcoRI site, detected in the mtDNA of two Dahe pigs, are the same as in the Vietnamese wild boar, suggesting that mutational hot spots exist in the mtDNA of pigs.