麂属(Muntiacus)动物MDR-1基因序列分析及其分子进化关系

对麂属（Muntiacus)中的3种动物：赤麂（M.muntjak)(2n-6♀,7♂）,小麂（M.reevesi)(2n=46),黑麂（M.crinifrons(2n=8♀,9♂）MDR－1基因（multidrug resistance,多药耐药基因）726bp左右的片段进行了序列分析并根据序列信息建立分子系统树,同时探讨了这3种动物的起源,分类地位及进化关系。     

苏姜猪及其杂交后代HSL基因PCR-RFLP分析

以苏姜猪、二元杂交猪（长白猪×苏姜猪、大白猪×苏姜猪）为研究对象,分别为60头,分析了HSL基因外显子Ⅰ区域PCR-RFLP多态性。结果表明,苏姜猪及其杂交后代群体中HSL基因外显子I中存在Bsa H I酶切片段长度多态性,均检测到AA、AB和BB基因型。苏姜猪群体中A等位基因占优势,频率为73.34%;杂交猪中B等位基因占优势,频率分别为56.66%和65.00%。研究结果丰富了苏姜猪的分子生物学研究,为苏姜猪的合理开发利用提供了依据。     

DNA分子进化的研究基础和策略

从研究方法和技术手段等方面讨论了分子进化研究上的一些重大问题．阐述了基因的基本结构及DNA分子的进化方式：净化选择、中性进化和分化选择。探讨了利用DNA分子进化数据构建系统树的原理,评价了NJ、UPGMAM、MP和ML4种算法在构建进化树时的合理性与不足,以及进化树可靠性检验的方法,并对未来分子进化生物学的发展加以展望。     

小菜蛾CYP6基因序列分析及其进化地位探讨

利用简并引物和特异性引物,通过RT-PCR和RACE技术,克隆出了一个小菜蛾细胞色素P450CYP6基因。该基因全长1661bp,编码区在26~1570位,翻译514个氨基酸,GenBank登录号为AY971374。分析该基因在昆虫CYP6基因家族系谱树中的位置和5′-UTR的序列,可以认为,小菜蛾CYP6基因与同为鳞翅目的其他昆虫进化地位相当,而明显与相对低等的蜚蠊目昆虫的同家族基因亲缘关系远。     

绵羊Cytb基因序列多态性及系统进化研究

以8个中国地方绵羊品种和1个外来品种的20个个体为研究对象,通过对Cytb基因的全序列测定,结果表明：绵羊的单倍型多样性为97．1％。所有序列的平均碱基组成为27．1％T,28．5％C,31．4％A及13．0％G,G＋C含量为41．5％,核苷酸多样性为0．602％。在所有序列中共检测到43个变异位点,其中包括40处转换和3处颠换。Fu’S中性检验表明差异不显著（0．10〉P〉0．05）,说明绵羊群体未发生群体扩张事件。NJ、ME及UPGMA聚类结果均表明,我国绵羊可分为3个单倍型组,这提示我国绵羊有3个母系起源。     

赤麂SRY基因的测序及其与部分偶蹄目动物SRY基因序列的比较

采用人SRY基因的一段保守序列的引物,通过PCR在雄性赤麂中扩增出了赤麂SRY基因的特异片段,通过DNA斑点杂交证实其扩增产物与人SRY基因探针进行菌落杂交筛选出赤麂SRY基因的阳性克隆,并对其进行了,将其序列与基因库中录入的所有偶蹄目动物的SRY基因序列进行同源性比较,用UPGMA法构建了其系统进化树,从分类和进化上对赤麂SRY基因进行分析。     

形目15种鸟类线粒体ND6基因序列差异及其系统进化关系

采用PCR和质粒克隆测序方法 ,首次获得形目 15种鸟类线粒体基因组的ND6基因全长 5 2 2bp的序列。经对位排列 ,序列间未见有插入和缺失 ,共有 2 16个变异位点 ,种间序列差异为 5 17%～ 19 92 %。以白鹳为外群 ,用NJ法构建 15种鸟类的进化关系树。研究结果表明 :构建的系统树将形目 15种鸟类分为 2个支系。第 1支系包括蒙古沙、环颈、灰斑和反嘴鹬。第 2支系包括红脚鹬、林鹬、青脚鹬、翘嘴鹬、翻石鹬、大滨鹬、尖尾滨鹬、斑尾塍鹬、中杓鹬、大杓鹬和白腰杓鹬 ,其中鹬属的 3个种和杓鹬属的 3个种分别组成一个单系 ;翘嘴鹬和翻石鹬、大滨鹬和尖尾滨鹬分别聚为姊妹群 ,表现出较近的亲缘关系 ;斑尾塍鹬独立分支出来。分子证据提示 :鹬科中的塍鹬属、科中的斑属应提升为亚科分类阶元 ;反嘴鹬与科鸟类亲缘关系较近 ,组成一个单系 ,将其归入科下属的一个类群更为合理 ,与核型研究结果及Sibley新分类体系的观点相一致 [动物学报 49(1) :6 1～ 6 7,2 0 0 3]。     

猪激素敏感脂肪酶(HSL)基因的研究概况

激素敏感脂肪酶(HSL)基因影响着脂肪的沉积,它在表达或活性上的轻微变异均有可能影响猪的背膘厚和瘦肉率。从激素敏感脂肪酶的功能及作用机制出发,通过候选基因策略克隆出HSL基因,将其精确定位于猪6号染色体6p1.1-1.2上;进而分析了HSL及其基因的分子结构,比较HSL基因在不同物种间的同源性。不同产肉型猪种间存在HSL基因的多态性,籍此可为了解猪脂肪沉积的基因效应、寻找与背膘厚及瘦肉率相连锁的分子标记提供通途,最终实现利用MAS、MAI等技术手段提高猪的瘦肉率。 Abstract:The gene affects the accumulation of lipid and its small variation on the activity or gene expression can influence the lean percentage and backfat traits.Based on the function and acting mechanism,this gene was cloned by candidate approach and located on the porcine chromosome 6P1.1～1.2.The molecular structure of HSL and HSL gene were analyzed.The homologies was attained by comparison between different mammal animals.The polymorphism of the gene in different pig breeds was detected.This will help the understanding of the genic effect on porcine fat deposition.The HSL gene should be regarded as a candidate gene for fatness in pis.It may have a potential use in MAS or MAI to increase the lean percentage of pig.     

鸻形目15种鸟类线粒体ND6基因序列差异及其系统进化关系

采用PCR和质粒克隆测序方法,首次获得鸻形目l5种鸟类线粒体基因组的ND6基因全长522bp的序列。经对位排列,序列间末见有插入和缺失,共有216个变异位点,种间序列差异为5．17％—19．92％。以白鹤为外群,用NJ法构建15种鸟类的进化关系树。研究结果表明：构建的系统树将鸻形目15种鸟类分为2个支系：第1支系包括蒙古沙鸻、环颈鸻、灰斑鸻和反嘴鹬。第2支系包括红脚鹬、林鹬、青脚鹬、翘嘴鹬、翻石鹬、大滨鹬、尖尾滨鹬、斑尾塍鹬、中杓鹬、大杓鹬和白腰杓鹬,其中鹬属的3个种和杓鹬属的3个种分别组成一个单系;翘嘴鹬和翻石鹬、大滨鹬和尖尾滨鹬分别聚为姊妹群,表现出较近的亲缘关系;斑尾塍鹬独立分支出来。分子证据提示：鹬科中的塍鹬属、鸻科中的斑鸻属应提升为亚科分类阶元;反嘴鹬与鸻科鸟类亲缘关系较近,组成一个单系,将其归入鸻科下属的一个类群更为合理,与核型研究结果及Sibley新分类体系的观点相一致。     

HSL基因重复多态与有氧耐力的关联性

目的:探讨激素敏感性脂肪酶(HSL)基因重复多态与有氧耐力之间的关联性。方法:采用PCR结合荧光标记复合STR-genescan方法,对123名中国北方汉族优秀长跑运动员与127名中国北方汉族普通大学生HSL基因第6内含子区(CA)n重复多态基因分型进行检测,对重复多态按分割点进行分组,划分为长、短链两个等位基因,卡方检验比较运动员组和对照组间等位基因频率和基因型频率差别。结果:HSL基因(CA)n重复多态共有9种不同重复次数的等位基因,组成25种不同基因型。卡方检验结果显示,当以4重复次数为分割点划分短链和长链等位基因进行比较时,基因型的分布在5/10 km组与对照组相比,有显著性差异(P0.05)。其余各组间进行比较,均无显著性差异。结论:HSL基因第6内含子(CA)n重复多态,当以4重复次数为分割点划分短链和长链等位基因进行比较时,LL基因型与有氧耐力相关联,可能是5/10 km运动员的分子标记。     

Phylogenetic analysis and classification of fossil and recent Alcelaphini Mammalia: Bovidae

Cladistic principles are applied to a group of antelope species, three-quarters of which are extinct. Only cranial and mandibular characters are used. The present phylogenetic hypothesis suggests diat the Alcelaphini are monophyletic; that the genera Parmularius and Damaliscus share a recent common ancestry; and that die extant Hunter's hartebeest should not be removed from Damaliscus into a separate genus Beatragus as several authors have done. A re-evaluation is suggested of die systematic position of Lichtenstein's hartebeest, as being phylogenetically closer to me wildebeests, genus Connochaetes , than to the type species of the hartebeest genus Alcelaphus. Some problems arising in the application of cladistic principles to such a low ranking group, treating die fossil majority exactly equivalently with recent taxa, are discussed. Comments on recency of common ancestry as it affects hybridization potential in bovids, on speciation and extinction rates arise.     

猪激素敏感脂酶和甘油三酯水解酶基因组织表达特性研究

以八眉猪为研究对象,采用RT-PCR和Western blot方法对猪激素敏感酯酶(HSL)和甘油三酯水解酶(TGH)基因组织表达特点进行了研究。RT-PCR半定量检测显示,HSL基因的mRNA在检测的7种组织中都有表达,其中在脂肪组织表达量较高,中等程度表达于心脏、肝脏、肺、脾和肾脏。TGH基因在7种组织也均有表达,其中肝脏和脂肪组织表达量较高,心脏和肾脏次之,脾脏和肺脏表达量较低。Western blot检测显示,HSL基因在大网膜脂肪和皮下脂肪表达量最高,而在肾脏中没有检测到表达,其他组织中中度表达;TGH基因在大网膜脂肪、皮下脂肪、肝脏、肺脏和脾脏组织中表达,其中在脂肪组织和肝脏组织中表达量最高,而在心脏和肾脏中没有检测到表达。以上结果表明:HSL和TGH基因存在转录后调控,这可能与其在不同组织中的功能差异有关。     

Molecular Phylogenies and Evolution of crt Genes in Algae

ABSTRACT

The carotenoids constitute the most widespread class of pigments in nature. Most previous work has concentrated on the identification and characterization of their chemical physical properties and bioavailability. In recent years, significant amounts of research have been conducted in an attempt to analyze the genes and the molecular regulation of the genes involved in the biosynthesis of carotenoids. However, it is important not to lose sight of the early evolution of carotenoid biosynthesis. One of the major obstacles in understanding the evolution of the respective enzymes and their patterns of selection is a lack of a well-supported phylogenic analysis. In the present research, a major long-term objective was to provide a clearer picture of the evolutionary history of genes, together with an evaluation of the patterns of selection in algae. These phylogenies will be important in studies characterizing the evolution of algae. The gene sequences of the enzymes involved in the major steps of the carotenoid biosynthetic pathway in algae (cyanobacteria, rhofophyta, chlorophyta) have been analyzed. Phylogenetic relationships among protein-coding DNA sequences were reconstructed by neighbor-joining (NJ) analysis for the respective carotenoid biosynthetic pathway genes (crt) in algae. The analysis also contains an estimation of the rate of nonsynonymous nucleotide substitutions per nonsynonymous site (d_N), synonymous nucleotide substitution per synonymous site (d_S), and the ratio of nonsynonmous (d_N/d_S) for the test of selection patterns. The phylogenetic trees show that the taxa of some genera have a closer evolutionary relationship with other genera in some gene sequences, which suggests a common ancient origin and that lateral gene transfer has occurred among unrelated genera. The d_N values of crt genes in the early pathway are relatively low, while those of the following steps are slightly higher, while the d_N values of crt genes in chlorophyta are higher than those in cyanobacteria. Most of the d_N/d_S values exceed 1. The phylogenetic analysis revealed that lateral gene transfer may have taken place across algal genomes and the d_N values suggest that most of the early crt genes are well conserved compared to the later crt genes. Furthermore, d_N values also revealed that the crt genes of chlorophyta are more evolutionary than cyanobacteria. The amino acids' changes are mostly adaptive evolution under the influence of positive diversity selection.     

Molecular Evolution of VEF-Domain-Containing PcG Genes in Plants

Arabidopsis VERNALIZATION2 （VRN2）, EMBRYONIC FLOWER2 （EMF2）, and FERTILIZATION-INDEPENDENT SEED2 （FIS2） are involved in vernalization-mediated flowering, vegetative development, and seed development, respectively. Together with Arabidopsis VEF-L36, they share a VEF domain that is conserved in plants and animals. To investigate the evolution of VEF-domain-containing genes （VEF genes）, we analyzed sequences related to VEF genes across land plants. To date, 24 full-length sequences from 11 angiosperm families and 54 partial sequences from another nine families were identified. The majority of the full-length sequences identified share greatest sequence similarity with and possess the same major domain structure as Arabidopsis EMF2. EMF2-1ike sequences are not only widespread among angiosperms, but are also found in genomic sequences of gymnosperms, lycophyte, and moss. No FIS2- or VEF-L36-1ike sequences were recovered from plants other than Arabidopsis, including from rice and poplar for which whole genomes have been sequenced. Phylogenetic analysis of the full-length sequences showed a high degree of amino acid sequence conservation in EMF2 homologs of closely related taxa. VRN2 homologs are recovered as a clade nested within the larger EMF2 clade. FIS2 and VEF-L36 are recovered in the VRN2 clade. VRN2 clade may have evolved from an EMF2 duplication event that occurred in the rosids prior to the divergence of the eurosid I and eurosid II lineages. We propose that dynamic changes in genome evolution contribute to the generation of the family of VEF-domain-containing genes, Phylogenetic analysis of the VEF domain alone showed that VEF sequences continue to evolve following EM F2NRN2 divergence in accordance with species relationship. Existence of EMF2-1ike sequences in animals and across land plants suggests that a prototype form of EMF2 was present prior to the divergence of the plant and animal lineages. A proposed sequence of events, based on domain organization and occurrence of intermediate seque     

Molecular phylogeny of caprines (Bovidae, Antilopinae): the question of their origin and diversification during the Miocene

Caprines include all bovids related to sheep and goat. The composition of the group is controversial and inter-generic relationships have been widely debated. Here, we analysed 2469 characters draw from three distinct molecular markers, i.e. two mitochondrial genes (cytochrome b and 12S rRNA) and one nuclear fragment (exon 4 of the κ -casein gene). The taxonomic sampling includes all genera putatively described as caprines, as well as several other bovid genera in order to elucidate the position of caprines within the family Bovidae, and to determine the exact composition of the group. Phylogenetic analyses confirm firstly that Pseudoryx and Saiga do not belong to caprines, and secondly, that all tribes classically defined in the literature are not monophyletic, supporting the inclusion of all caprine species into a unique enlarged tribe Caprini sensu lato . Our results are in contradiction with previous investigations suggesting a sister-group relationship between Ovis (sheep and mouflons) and Budorcas (takins). By using a molecular calibration point at 18.5 Mya for the first appearance of bovids, we estimated divergence times with our molecular data. We also performed biogeographic inferences to better understand the origin and diversification of caprines during the Neogene. Our analyses suggest that caprines shared a common ancestor with Alcelaphini and Hippotragini in the middle-late Miocene (13.37 ± 0.70 Mya). Our results also indicate that the extant generic diversity of caprines resulted from a rapid adaptive radiation during the late Miocene, at 10.96 ± 0.73 Mya. We propose that this adaptive radiation resulted from the acquisition of reduced metacarpals, a key innovation which occurred during the late Miocene as a consequence of insularity isolation in the mountainous mega-archipelago between Mediterranean and Paratethys Seas.     

miRNA-9基因家族进化分析及其靶基因预测

microRNAs(miRNA)是真核生物中一类长度约为21～25个核苷酸的非编码小分子RNA,在转录后水平调控基因的表达。该文在miRBase中搜索后生动物的mir-9基因序列。47个物种中共搜索到120条mir-9基因序列,说明mir-9基因家族广泛存在于不同物种中。基因定位显示86%的mir-9基因存在于基因间隔区(IGR),多序列比对发现miR-9基因家族成熟序列的第2位到第8位碱基以及第14位到第18位碱基为保守碱基。进化分析表明mir-9b和mir-9c可能是此基因家族最早出现的基因形式,即祖先基因。这些祖先基因经过串联重复、大片段重复、个别碱基的缺失及突变等方式形成了脊椎动物中miR-9-1至miR-9-7数个基因。分别采用四个miRNA靶基因预测软件对mmu-miR-9的靶基因进行预测,发现miR-9与神经系统发育、心肌系统疾病和跨膜运输系统等密切相关。该研究为今后进一步研究miRNA调控的神经系统发生和神经细胞生长与分化的机制奠定了基础。     

猪激素敏感脂肪酶基因外显子1的遗传多态性分析

采用PCR-SSCP方法检测猪激素敏感脂肪酶（hormone sensitive lipase,HSL）基因外显子1的多态性,并分析其与初生重、断奶重、6月龄重和背膘厚的关联性。根据猪HSL基因的DNA序列（AJ000483）设计5对引物,结果在P5引物对扩增的片段上发现了多态性,并对纯合子进行测序,发现外显子1的874bp处存在G-A转换,且存在3种基因型（AA、AB、BB）。统计结果表明,3种基因型在各品种中的分布不一致,长白猪和大白猪与莱芜猪和沂蒙黑猪比较差异极显著（P〈0．01）,长白猪与大白猪比较,莱芜猪与沂蒙黑猪比较差异均不显著（P〉0．05）。固定效应模型分析结果表明,背膘厚基因型间差异显著（P〈0．05）,而初生重、断奶重和6月龄重基因型间差异均不显著（P〉0．05）。最小二乘分析结果表明,BB基因型个体同AB和AA基因型个体比较背膘厚的差异显著（P〈0．05）,3种基因型在背膘厚的大小排列顺序为BB〈AB〈AA。因此,推测HSL基因对个体胴体瘦肉率存在一定的影响将HSL某因应用于猪育种过程中的标记辅助选择可以加快猪的育种进程。     

形目12种鸟类线粒体细胞色素b基因序列差异及其系统发育关系

采用PCR直接测序方法首次对形目 (Charadriiformes) 12种鸟类 :蒙古沙 (Charadriusmongolus)、环颈(Charadriusalexandrinus)、大杓鹬 (Numeniusmadagascariensis)、白腰杓鹬 (Numeniusarquata)、中杓鹬 (Numeniusphaeo pus)、红脚鹬 (Tringatotanus)、林鹬 (Tringaglareola)、翘嘴鹬 (Xenuscineres)、翻石鹬 (Arenariainterpres)、大滨鹬 (Calidristenuirostris)、反嘴鹬 (Recurvirostraavosetts)和砺鹬 (Haematopusostralensis)线粒体cytb基因全序列进行测定 ,并以白鹳(Ciconiaciconia)的同源序列作为外群构建系统发生树。经比对 ,形目 12种鸟类线粒体cytb基因全序列均包括1143bp ,序列间未见有插入和缺失 ,共有 381个变异位点 ,种间序列差异值为 5 16 %～ 16 0 1%。重建的系统树将形目 12种鸟类分为 2个支系 :第 1支系包括红脚鹬、林鹬、翻石鹬、大滨鹬、翘嘴鹬、中杓鹬、大杓鹬和白腰杓鹬 ,其中红脚鹬、林鹬、翻石鹬、大滨鹬、翘嘴鹬聚为一支 ,中杓鹬、大杓鹬和白腰杓鹬聚为另一支 ;第 2支系包括蒙古沙、环颈、反嘴鹬和砺鹬 ,其中反嘴鹬与砺鹬互为姐妹群 ,然后再与属的两个种蒙古沙和环颈组成的姐妹群构成并系群。分子证据提示 :第 1支系中各属间及种间的系统关系与形态学研