大熊猫生长激素受体(GHR) cDNA 的克隆与序列分析

根据已报道的若干物种GHR 基因cDNA 序列设计引物, 利用RT- PCR 技术首次从大熊猫肝脏组织总RNA中扩增出GHR 基因编码区全长cDNA 序列, 克隆于pGEM®-T 载体后进行测序和序列分析。结果表明,大熊猫GHR 的ORF为1 917 bp , 编码638 个氨基酸的前体蛋白, 由18 个氨基酸的信号肽和620 个氨基酸的成熟肽组成,与人、狗、猪GHR 结构相似, 大熊猫GHR 成熟肽由246 个氨基酸的胞外区、24 个氨基酸的跨膜区和350 个氨基酸的胞内区组成, 并具GHR 的特征性结构。序列相似性比较显示, 大熊猫GHR 与哺乳类GHR 具有69 %～93 %的高序列相似性, 与爬行类和鸟类的序列相似性也达到60 % , 而与鱼类的序列相似性较低, 仅为30 %左右。与其它哺乳动物GHR 相比, 大熊猫GHR 在氨基酸序列上也存在明显的特异性。     

白鱀豚的肾脏

研究了4头雄性和9头雌性白鱀豚肾脏的结构和各项指标。白鱀豚肾脏是由许多小肾组成。肾脏和小肾的各项指标随着个体体长的增加而增加。与其他3种淡水豚相比,白鱀豚成体肾脏的小肾数比恒河豚多,比哑河豚少,而与拉河豚相近。白鱀豚幼体的肾脏和小肾的各项指标与恒河豚和亚河豚相近,但成体肾脏和小肾的各项指标比上述2种淡水豚大得多。并证实鲸类动物肾脏的小肾并生群在幼体即已存在,随着个体的长大,小肾化加剧,而并不是次级融合的结果。白鱀豚小肾的髓旁肌肉带的排列并无规律,它并不构成白豚鱀所特有的排列结构。       

中国科学院水生生物研究所鲸类保护生物学学科组简介

鲸类保护生物学学科组的前身是1978年秋成立的白鱀豚研究组。本学科组致力于白鱀豚、江豚、中华白海豚和扬子鳄等国家重点保护水生珍稀野生动物的保护生物学研究,重点研究濒危动物致危的内部与     

白鱀豚脑的解剖

作者对采自长江的三头白鱀豚(Lipotes vexillifer Miller)的脑进行了解剖研究。白鱀豚的脑表现出典型的鲸脑特征。与海洋齿鲸类比较,淡水鲸科的种类普遍呈现出视觉系统的退化,这是一种生态适应的结果。从神经解剖学的观点看来,白鱀豚与亚马逊河海豚(Inia)、拉普拉塔河海豚(Pontoporia)的脑的结构是近似的,而与恒河海豚(Platanista)显著不同,这与骨骼形态上表现出的系统发育关系是一致的。       

绞股蓝鲨烯环氧酶基因的克隆与序列分析

根据已报道植物鲨烯环氧酶(squalene epoxidase,SE)基因cDNA序列的保守区域设计引物,利用RT-PCR和RACE技术,对绞股蓝SE基因进行克隆及序列分析.结果表明,绞股蓝SE基因cDNA全长为1 818 bp,编码一个由525个氨基酸残基组成的多肽.绞股蓝SE基因编码的氨基酸序列中含有52.4%的非极性疏水性氨基酸,26.1%极性中性氨基酸,9.0%酸性氨基酸,12.6%碱性氨基酸.Blast结果显示,绞股蓝SE基因核苷酸序列与其他已报道的植物SE基因相似性为73%～82%,推导的氨基酸序列相似性为63.2%～79.4%.SE氨基酸序列进化分析发现,绞股蓝SE与绿珊瑚、拟南芥亲缘关系较近.     

白鱀豚脑的解剖

作者对采自长江的三头白暨豚(Lipotes vexillifer Miller)的脑进行了解剖研究。白鱀豚的脑表现出典型的鲸脑特征。与海洋齿鲸类比较,淡水鲸科的种类普遍呈现出视觉系统的退化,这是一种生态适应的结果。从神经解剖学的观点看来,白鱀豚与亚马逊河海豚(Inia)、拉普拉塔河海豚(Pontoporia)的脑的结构是近似的,而与恒河海豚(Platanista)显着不同,     

鲸类分子系统学研究进展

综述了近年来分子生物学标记技术在鲸类系统学研究中的进展。分子生物学证据支持鲸目与有蹄类之间有较近的亲缘关系,并支持鲸类的单系起源,但鲸类不同类群(须鲸类、抹香鲸类及不包括抹香鲸类的齿鲸类)之间的系统发生关系仍存在争议。抹香鲸类到底与须鲸类还是与其它齿鲸类有更近的亲缘关系,不同的分子生物学家所得到的结果并不一致。此外,分子生物学技术还被用于解决须鲸亚目和齿鲸亚目内科间以及科内种间的系统发生关系,特别是齿鲸亚目的海豚科、鼠豚科和淡水豚类。通过分子标记技术来研究鲸类种下的遗传结构是鲸类分子系统学研究中的一个新热点,使用的标记主要是mtDNA控制区、核DNA微卫星和主要组织相容性复合体(major histo-compatibilitv complex,MHC)等。     

藏羚羊组蛋白去乙酰化酶1 基因编码区的克隆与序列分析

为探讨藏羚羊的低氧适应机制与高原低氧环境的相关性,采用RT-PCR 技术,首次从藏羚羊心肌组织总DNA 中克隆出组蛋白去乙酰化酶1 (Histone deacetylase1,HDAC1)基因的编码区序列。该序列全长为1 449 bp,
编码482 个氨基酸,预测其蛋白质分子量约为55 kDa。序列分析表明,藏羚羊HDAC1 基因的编码区序列与其它哺乳动物相似性超过90% ,其中与牛的相似性最高为98.27% ;它的氨基酸序列与其它哺乳动物的相似性达到
98.76% ～ 99.59%,显示出极高的保守性。利用邻接法(Neighbor-Joining,NJ 法)构建的分子系统进化树聚类结果表明,藏羚羊与牛先聚为一类,该聚类结果与传统的物种进化关系基本一致。藏羚羊HDAC1 基因编码区的成
功获得,为进一步揭示藏羚羊低氧适应的表观遗传机制奠定基础。     

一条河流的挽歌——物种灭绝、气候变迁及长江生物多样性保护的最后希望

<正>淡水生物多样性受到全球性威胁,在世界上大型河流中生存的一些体型最大的、最有魅力的物种正在面临灭绝。其中一个标志性的物种是白鱀豚,它已于2007年被公布成为第一个因为人类活动造成功能性灭绝的鲸类物种。作为白鱀豚科唯一的代表物种,它的灭绝标志着一个进化枝系的消失。不幸的是,白鱀豚只是长江众多受到严重威胁的物     

中国近海鲸类的分布

中国近海鲸类的资源分布过去未曾进行过全面系统的调查,除黄海产的须鲸类和长江的白鱀豚近年作了些深入研究外,其余只有一些简单报道和记载。本文是作者在接受中国海洋珍稀哺乳动物调查任务后,根据多年来的调查资料,并参考有关文献,经过整理、分析而写成。     

谷子肌动蛋白基因的克隆及序列分析

以谷子 (Setariaitalica)为材料 ,提取总RNA。根据植物肌动蛋白基因编码区的两端的保守序列设计了简并引物 ,用 5’RACE方法扩增出了谷子肌动蛋白基因编码区序列。以豌豆肌动蛋白cDNA作探针进行的Southern杂交分析表明扩增出了目的基因。将所获得的片段克隆到T载体后进行测序 ,序列分析结果表明 :谷子肌动蛋白基因的编码区长 1 1 3 1个核苷酸 ,编码了 3 77个氨基酸 ;所得序列 (命名为MIAc)与GenBank中注册的肌动蛋白基因序列的相似性均在 6 0 %以上 ,与其它肌动蛋白氨基酸序列的相似性达 89%以上。根据高等植物肌动蛋白序列相似性重建了进化树 ,表明谷子肌动蛋白与水稻肌动蛋白异型体RAc2和RAc3之间的亲缘关系最为密切 ,在进化过程中分化时间最为接近     

Nucleotide sequence and molecular characterization of the structural glycoprotein gp41 gene homologue of Spodoptera litura nucleopolyhedrosis virus (spltNPV-I)

The structural glycoprotein gene gp41 homologue of Spodoptera litura nucleopolyhedrosis virus (SpltNPV-I *) was identified in the 4.0 kb EcoRI-L fragment of the viral genome. The nucleotide sequence of 2063 bp of this fragment revealed an open reading frame of 1014 nucleotides to encode a polypeptide of 337 amino acids. Analysis of nucleotide and deduced amino acid sequences of the putative ORF indicated its identity with gp41 protein of other baculoviruses sharing maximum homology with that of Spodoptera frugiperda nucleopolyhedrosis virus (SfNPV). The coding sequence was preceded by an AT-rich region containing the consensus baculoviral late promoter motif RTAAG. The putative SpltNPV gp41 ORF was abundantly expressed as a 37 kDa apoprotein in E. coli and as a 50 kDa glycoprotein in Sf9 cells. The recombinant protein expressed in insect cells was glycosylated (20%) and has GlcNAc as the terminal sugar. The gene is conserved among baculoviruses and places SpltNPV-I close to Spodoptera frugiperda and Spodoptera exigua NPVs in phylogenetic tree.     

Phylogenetic relationships of aquatic birnaviruses based on deduced amino acid sequences of genome segment A cDNA.

Aquatic birnaviruses, such as infectious pancreatic necrosis virus (IPNV), cause serious diseases in a variety of fish species used worldwide in aquaculture and have also been isolated from a variety of healthy fish and shellfish species. These viruses exhibit a high degree of antigenic heterogeneity and variation in biological properties such as pathogenicity, host range, and temperature of replication. To better understand genetic and biological diversity among these viruses, the nucleotide and deduced amino acid sequences were determined from cDNA of the large open reading frame (ORF) of genome segment A of the 9 type strains of Serogroup A and 4 other representative strains of Serotype A1, the predominant serotype in the United States. In addition, nucleotide and deduced amino acid sequences were determined for the VP2 coding region of a variety of isolates representing 5 of the 9 serotypes. VP2 is the major outer capsid protein of aquatic birnaviruses. RT-PCR was used to amplify a 2904 bp cDNA fragment including all but a few bp of the large ORF of genome segment A or a 1611 bp fragment representing the entire VP2 coding region. Nucleotide and deduced amino acid sequences were determined from the PCR products. Pairwise comparisons were made among our data and 2 other aquatic birnavirus sequences previously published. Several hypervariable regions were identified within the large ORF. The most divergent pair of viruses exhibited a similarity of 80.1% in the deduced amino acid sequence encoded by the large ORF. Genomic relationships revealed in a phylogenetic tree constructed from comparison of the deduced amino acid sequences of the large ORF demonstrated that these viruses were clustered into several genogroups. Phylogenetic comparison of the deduced amino acid sequences of the VP2 coding region of 28 aquatic birnavirus isolates, including the type strains of all 9 serotypes, demonstrated 6 genogroups, some of which were comprised of several genotypes. The most divergent pair of viruses exhibited a similarity of 81.2% in the deduced amino acid sequence from the VP2 coding region. In contrast to previous studies of much shorter genomic sequences within the C-terminus-pVP2/NS junction coding region, these genogroups based on the entire large ORF or the VP2 coding region generally correlated with geographical origin and serological classification. Isolates from the major Canadian serotypes were more closely related to the European isolates than to isolates from the United States.     

谷子肌动蛋白基因的克隆及序列分析

以谷子（Setaria italica）为材料,提取总RNA。根据植物肌动蛋白基因编码区的两端的保守序列设计了简并引物,用5'RACE方法扩增出了谷子肌动蛋白基因编码区序列。以豌豆肌动蛋白cDNA作探针进行的Southern杂交分析表明扩增出了目的基因。将所获得的片段克隆到T载体后进行测序,序列分析结果表明：谷子肌动蛋白基因的编码区长1131个核苷酸,编码了377个氨基酸;所得序列(命名为MIAc)与GenBank中注册的肌动蛋白基因序列的相似性均在60%以上,与其它肌动蛋白氨基酸序列的相似性达89%以上。根据高等植物肌动蛋白序列相似性重建了进化树,表明谷子肌动蛋白与水稻肌动蛋白异型体RAc2和RAc3之间的亲缘关系 最为密切,在进化过程中分化时间最为接近。     

Nucleotide sequence and molecular characterization of the structural glycoprotein gp41 gene homologue of <Emphasis Type="Italic">Spodoptera litura</Emphasis> nucleopolyhedrosis virus (SpltNPV-I)

The structural glycoprotein gene gp41 homologue of Spodoptera litura nucleopolyhedrosis virus (SpltNPV-I *) was identified in the 4.0 kb EcoRI-L fragment of the viral genome. The nucleotide sequence of 2063 bp of this fragment revealed an open reading frame of 1014 nucleotides to encode a polypeptide of 337 amino acids. Analysis of nucleotide and deduced amino acid sequences of the putative ORF indicated its identity with gp41 protein of other baculoviruses sharing maximum homology with that of Spodoptera frugiperda nucleopolyhedrosis virus (SfNPV). The coding sequence was preceded by an AT-rich region containing the consensus baculoviral late promoter motif RTAAG. The putative SpltNPV gp41 ORF was abundantly expressed as a 37 kDa apoprotein in E. coli and as a 50 kDa glycoprotein in Sf9 cells. The recombinant protein expressed in insect cells was glycosylated (20%) and has GlcNAc as the terminal sugar. The gene is conserved among baculoviruses and places SpltNPV-I close to Spodoptera frugiperda and Spodoptera exigua NPVs in phylogenetic tree.Assigned GenBank accession no. for the nucleotide sequence data is AF445192.abbreviated as SlNPV in earlier publications and GenBank     

Nucleotide sequence of a Madagascar hepatopancreatic parvovirus (HPV) and comparison of genetic variation among geographic isolates

A segment of Madagascar hepatopancreatic parvovirus (HPV) genomic sequence (5742 nucleotides) was determined through PCR and direct sequencing. This nucleotide sequence was compared to isolates from Australia, Thailand, Korea, and Tanzania, and the mean distance was determined to be 17%. The Madagascar HPV is closest to the Tanzania isolate (12%), followed by isolates from Korea (15%), Australia (17%) and Thailand (20%). Analysis of the genomic structure revealed that this HPV sequence is comprised of one partial Left open reading frame (ORF) (349 amino acids, aa) and complete Mid (578 aa) and Right (820 aa) ORFs. The amino acid sequences of the 3 ORFs were compared among isolates. The Right ORF was found to have the highest variation with a mean distance of 24%. This was followed by the Left and Mid ORF with distances of 13 and 7%, respectively. A phylogenetic analysis based on the amino acid sequence of the Right ORF divides 7 HPV isolates into 3 well-separated groups: Korea, Thailand, and Australia. The Madagascar HPV clustered with the Korea and Tanzania isolates. In Madagascar, HPV has been detected by histological examination since the 1990s. PCR analysis of a recent (2007) sampling showed a 100% prevalence. HPV was also detected in Mozambique with a 100% prevalence. High (95%) prevalence of HPV was found in wild Penaeus merguinesis collected from New Caledonia. These results indicate that HPV displays a high degree of genetic diversity and is distributed worldwide among populations of penaeid shrimp.     

The genes coding for the L,M and cytochrome subunits of the photosynthetic reaction center from the thermophilic purple sulfur bacterium t Chromatium tepidum

The complete nucleotide sequences of the genes coding for L, M protein subunits and part of cytochrome subunit of the photosynthetic reaction center were determined for the thermophilic purple sulfur bacterium t Chromatium tepidum (t Chr. tepidum) which belongs to the subclass. The DNA fragments with 860 bp and 1900 bp were amplified by the Polymerase Chain Reaction (PCR) with the primers designed on the basis of amino acid sequences according to chemical sequence analysis of the proteins. The deduced amino acid sequences of these genes showed a significantly high degree of homology with those from purple non-sulfur bacteria. The L subunit consisted of 280 amino acids and had a molecular mass of 31,393. The M subunit consisted of 324 amino acids and had a molecular mass of 36,299. The aligned sequences of the L subunits of other purple bacterial reaction center polypeptides, showed the insertion of 8 amino acids in t Chr. tepidum in the connection of the first and second membrane-spanning helices different from those of purple non-sulfur bacteria. The aligned sequences of the L, M and cytochrome subunits were compared with other species and discussed in terms of phylogenetic trees.     

山茶属CHS基因家族的组成和分子进化初探

用PCR方法从4种山茶属(Camellia)(山茶科)(Theaceae)植物的总DNA中分别扩增到CHS基因外显子2的部分序列,经克隆、测序得到16个该基因的序列,这些序列与来自GenBank的该属另一种植物的3个序列及作为外类群的大豆(Glycine max (L.) Merr.)的2个序列一起进行分析.研究表明,山茶属CHS基因家族在进化过程中已分化为A、B、C三个亚家族,包括A1、A2、A3、B1、B2、C 等6类不同的基因成员;其中只有A2类成员为全部被研究的5种植物所共有,而其他5类成员只在部分被研究的植物中发现;所有这些CHS成员具有很高的同源性:在核苷酸水平上同一亚家族内基本上高于90%,不同亚家族间也在78%以上.从推测的氨基酸组成看,山茶属内CHS基因的功能已发生了分化,各类成员的碱基替代率有较大差异; 从分子系统发育树和可能的氨基酸组成分析,山茶属具有新功能的基因成员是在经过基因重复后,或是由少数几个位点的突变而成,或是由逐渐积累的突变而形成的.进一步分析认为,该属CHS基因的分化直到近期还在活跃地进行,并且不同种的进化式样有一定的差别,这种不同的进化式样可能是物种形成后受不同环境因素影响而形成的.