用12SrRNA基因序列研究潮龟科（BATAGURIDAE）闭壳龟类的进化

测定了潮龟科（Ｂａｔａｇｕｒｉｄａｅ）具闭壳结构的齿缘摄龟属（Ｃｙｃｌｅｍｙｓ）、锯缘摄龟属（Ｐｙｘｉｄｅａ）、闭壳龟属（Ｃｕｏｒａ）共６种线粒体１２ＳｒＲＮＡ基因片段的序列,结合潮龟科其它一些属的序列数据,探讨了具闭壳结构龟类的起源与进化以及闭壳龟属的分类学问题．认为闭壳龟属与锯缘摄龟属为姐妹群,两者与齿缘摄龟属的亲缘关系较远,提示这些具闭壳结构的龟类可能不是由一个共同祖先分化而来．本文的结果不支持将闭壳龟属拆分为闭壳龟属和盒龟属两属     

大熊猫与熊类动物性别的分子鉴定

根据已知动物的性别决定因子基因序列设计引物,以非性别特异性的脑源性神经营养因子基因片段（ＢＤＮＦ）作为正对照,用于扩增大熊猫、浣熊、天山棕熊和马来熊个体的ＳＲＹ（ｓｅｘｄｅｔｅｒｍｉｎｉｎｇｒｅｇｉｏｎｏｎＹｃｈｒｏｍｏｓｏｍｅ）基因片段并对其进行凝胶电泳分析,由此建立了一套简单、快速、可靠的动物性别分子鉴定方法．该方法不仅有利于尽快确定大熊猫等珍稀濒危动物的性别,而且也可以用于野外种群的性别比例调查．     

中国茸鹿品种(品系)的随机扩增多态DNA(RAPD)研究

采用随机扩增多态ＤＮＡ技术研究了５个茸鹿品种（品系）７５个个体的遗传变异关系。在所使用的４１个引物中，有４０个引物扩增出多态谱带，共检测到３９５条扩增片段，其中２５９条（６５．６％）出现变异，用Ｓｈａｋｎｎｏｎ指数计算了５个品种（品系）的遗传变异及其遗传变异在群体内和群体间的分布。利用Ｎｅｉ氏片段共享度计算了７５个个体间的遗传距离，用ＵＰＧＭＡ聚类法构建了７５个个体的系统发育树状图，反映５个茸鹿品     

游蛇科（Colubridae）10种蛇的随机扩增多态DNA研究

用随机扩增多态ＤＮＡ（ＲＡＰＤ）技术对游蛇科１０种蛇基因组ＤＮＡ的多态性进行了分子遗传标记的研究．所得数据经聚类分析结果提示：１．蛇类种内个体间存在着遗传多样性即个体间的差异，随机扩增多态ＤＮＡ片段共享度的分析表明，种间差异显著大于种内个体间的差异，说明在研究种间系统演化关系时．可以用随机取样的个体代表一个种作种间比较．２．锦蛇属是一高度分化的大属，本研究中的５种锦蛇间．玉斑锦蛇和红点锦蛇关系较近．可以井为１组．另３种归为１组还是分为３个不同的组尚难定论．３．游蛇科６个属之间．锦蛇属、乌梢蛇属和鼠蛇属３属间亲缘关系较近．Ｒｈａｂｏｐｈｉｓ和Ｓｉｎｏｎａｔｒｉｘ与链蛇属较近．它们可能代表该科中较原始的类群．     

用简并引物扩增与克隆D.radiodurans超氧化物歧化酶和过氧化氢酶基因片段

依据超氧化物歧化酶（ＳＯＤ） 和过氧化氢酶（Ｃａｔ） 的保守性氨基酸序列,设计简并引物,自Ｄ．ｒａｄｉｏｄｕｒａｎｓ 基因组ＤＮＡ扩增并克隆了ＳＯＤ和Ｃａｔ 基因片段．ＳＯＤ 和Ｃａｔ 基因片段分别长４５３ ｂｐ 和６７３ ｂｐ,各编码１５１和２２４ 个氨基酸,氨基酸序列与不同生物来源的ＳＯＤ或Ｃａｔ 具有高度同源性     

用单个特异引物扩增桃ACC氧化酶cDNA及其在大肠杆菌中的表达

用单个特异引物和通用引物ｏｌｉｇｏ（ｄＴ）１５从桃受伤叶片ｃＤＮＡ中扩增出１．３ｋｂ左右大小的片段．将该扩增产物克隆并对重组克隆作酶切分析发现至少可分为３类．用桃ＡＣＣ氧化酶基因组ＤＮＡ为探针进行点杂交表明,４,７,９,１０,１１,１２重组质粒能与之杂交,其中７,９,１０,１１,１２号重组质粒酶切图谱与已报导的桃果实成熟相关的ＡＣＣ氧化酶ｃＤＮＡ基因基本一致,而４号克隆则不同．ＤＮＡ序列分析和ＰＣＲ鉴定表明,插入片段均由５′端特异引物单个引物扩增出来,对７号重组克隆插入片段ＤＮＡ全序列分析表明,７号重组克隆插入片段全长１１４６ｂｐ,包含了除启始密码子外的全部编码区和１９２ｂｐ的３′端非编码区．通过补上起始密码子ＡＴＧ构建重组表达载体,在大肠杆菌中表达出３５×１０３的非融合蛋白     

游蛇科（Colubridae）10种的随机扩增多态DNA研究

用随机扩增多态ＤＮＡ（ＲＡＰＤ）技术对游蛇科１０种蛇基因组ＤＮＡ的多态性进行了分子遗传标记的研究，所得数据经聚类分析结果提示，１．蛇类种内个体间在着遗传多样性妈个体间的差异，随机扩增多态ＤＮＡ片段共享度的分析表明，种间差异显著大于种内个体间的差异，说明在研究种间系统演化关系时，可以用随机取样的个体代表一个种作种间的比较．２．锦蛇属是一高度分化的大属，本研究中的５种锦蛇间，玉斑锦蛇和红点锦蛇关系的较     

苏云金芽胞杆菌菌株WB9编码活性因子的基因分析

采用PCR—RFLP及PCR技术对苏云金芽胞杆菌新分离菌株WB9的ICP、VIP、几丁质酶和肠毒素4种活性因子的编码基因进行了分析．结果表明，该菌株含有编码ICP的cry1Aa、cry1Ab、cry1Cb、cry1Fa和cry1GaS个cry1基因型，编码Vip3A蛋白的vip3A基因以及编码3种肠毒素的hblA、bceT和entS基因；不含编码几丁质酶的基因．将vip3A、hblA、bceT和entS基因PCR产物回收纯化后直接测序，经在线的BLAST软件进行同源性分析，前两个基因片段与Bt已公布基因序列的相应片段同源性分别为99％和96％～98％，bceT基因片段与蜡质芽孢杆菌bceT相应片段同源性为97％．     

用简并引物扩增与克隆D.radiodurans超氧化物歧化酶和过氧化 …

依据超氧化物歧化酶（ＳＯＤ）和过氧化氢酶（Ｃａｌ）的保守性氨基酸序列,设计简并引物,自Ｄ．ｒａｄｉｏｄｕｒａｎｓ基因组ＤＮＡ扩增并克隆了ＳＯＤ和Ｃａｔ基因片 Ｃａｔ基因片段分别长４５３ｂｐ和６７３ｂｐ,各编码１５１和２２４个氨基酸,氨基酸序列与不同生物来源的ＳＯＤ或Ｃａｔ具有高度同源性。     

盐胁迫下耐盐与盐敏感水稻的RAPD和POD同工酶检测

对耐盐、一般耐盐和盐敏感３种水稻材料进行了ＲＡＰＤ和同工酶检测，结果发现：３３个引物（Ｎ－１－Ｎ－１２，Ｓ４５０－Ｓ４７０）中，２７个引物具有拉增产物，拉增片段大小分布在０．２－３．４ｋｂ之间，说明在一定程度上反映了３种对盐具有不同耐盐性水稻在基因组ＤＮＡ分子水平上的差异，以Ｓ４５０为引物，在强耐盐的７７９中扩增出１个１．１ｋｂ的特异ＤＮＡ片段（Ｓ４５０１１００），而在对盐敏感的早花２号中，以Ｎ－     

大凉疣螈脑源性神经营养因子(BDNF)基因的克隆与序列分析

大凉疣螈 (Ｔｙｌｏｔｏｔｒｉｔｏｎｔａｌｉａｎｇｅｎｓｉｓ)属于两栖纲有尾目蝾螈科 ,仅分布在我国四川省西南部 ,活动范围狭窄 ,数量有限 ,是我国二级保护动物[1] .两栖动物在生物进化中是承上启下的关键动物 ,它们开启了脊椎动物登上陆地的历史 ,而且是真正陆生脊椎动物—爬行动物的祖先 ,其生理、结构等方面与鱼类和爬行类都有着明显的差别 .脑源性神经营养因子 (ｂｒａｉｎ ｄｅｒｉｖｅｄｎｅｕｒｏｔｒｏｐｈｉｃｆａｃｔｏｒ,ＢＤＮＦ)是神经营养因子家族的一员 ,ＢＤＮＦ在脊椎动物胚胎神经系统的发育、分化及在成体神经系统维…     

Assessment of non-invasive techniques for monitoring mercury concentrations in species of Amazon turtles

This study determined the concentrations of mercury (Hg) in four tissues of six species of turtles from the Rio Negro in the Amazon Basin. For two species, blood and carapace tissues were correlated with concentrations in internal tissues to establish whether blood or carapace could serve as a non-lethal indicator of internal metal exposure or body burden. The four tissues’ Hg levels were also correlated to turtle size and gender. The liver in five species of turtles had the highest concentration, followed by carapace, muscle, and blood. The exception was Chelus fimbriatus, which had a higher metal concentration in the muscle than carapace. Regarding the correlation between total Hg concentrations in tissues of the two species, no significant correlation was noted for Podocnemis erythrocephala. However, for Podocnemis sextuberculata significant correlation was found between muscle?×?liver, muscle?×?blood, and liver?×?blood. For P. erythrocephala, there was a correlation between Hg concentration in carapace and turtle size. For P. sextuberculata, there was no marked correlation between Hg concentration and size, but concentration in muscle was significantly influenced by gender. The patterns of Hg accumulation in tissues of the five species followed those described for freshwater species and some species of sea turtles. The difference in C. fimbriatus may be a result of a different pattern of non-living keratin layers on the carapace tissue. The use of carapace to infer internal concentrations of Hg is common in freshwater and sea turtles, but in this study it was found that only blood might be a reliable indicator of Hg concentrations in liver and muscle tissues for P. sextuberculata. Thus blood may be used as a non-invasive method to study concentrations of Hg in liver and muscle of P. sextuberculata.     

DNA Fingerprinting Reveals a Lack of Genetic Variation in Northern Populations of the Western Pond Turtle (Clemmys marmorata)

I used DNA fingerprinting to provide the first analysis of the genetic composition of western pond turtle ( Clemmys marmorata ) populations in Washington, Oregon, and California. Populations of the western pond turtle in Washington and northern Oregon are rapidly approaching extinction. Genetic similarity within the largest northern populations, which are located inland, is high. An analysis of population substructure (F_st) revealed significant genetic divergence between inland populations, indicating a lack of dispersal and gene flow between sites. In contrast, northern coastal sites are not genetically distinct, but there are few if any viable populations remaining in this region. Genetic variability within southern California populations is a great deal higher than in northern inland sites. Similarly, a low F_st value indicated a lack of genetic differentiation between southern sites. An inter-regional analysis of population substructure (F_st = 0.24) revealed a significant degree of genetic divergence between geographical regions throughout the range. In addition, an estimate of western pond turtle phylogeny showed a genetic break in the species between northern and southern populations. Both population subdivision and phylogenetic analyses suggest a lack of appreciable gene flow between geographical regions for a considerable period of time. Genetic analyses support traditional subdivision based solely on the morphological variation of Clemmys marmorata into two subspecies: northern Clemmys marmorata marmorata and southern Clemmys marmorata pallida . Recovery of dwindling northern populations must combine demographic and genetic considerations. A first step should be to preserve local gene pools while augmenting population numbers, with the goal of preventing the extinction of this genetically and morphologically distinct subspecies.     

Patterns in the emergence of green (<Emphasis Type="Italic">Chelonia mydas</Emphasis>) and loggerhead (<Emphasis Type="Italic">Caretta caretta</Emphasis>) turtle hatchlings from their nests

The emergence patterns of both green (Chelonia mydas) and loggerhead (Caretta caretta) turtle hatchlings were observed in great detail over three seasons at Alagadi beach, northern Cyprus. In total, 38 green turtle and 50 loggerhead turtle nests were monitored, accounting for the emergence of 2,807 and 2,259 hatchlings, respectively. We quantified these emergences into 397 green turtle and 302 loggerhead turtle emergence groups. Overall, 85.0% of green turtle and 79.5% of loggerhead turtle groups emerged at night; these accounted for 85.5 and 90.8% of hatchlings, respectively. The remaining emergences were dispersed throughout the day for green turtle nests but confined to the morning in loggerhead turtle nests. Hatchling emergence from individual nests occurred over periods of between 1 and 7 nights, with most hatchlings typically emerging on the first night. Group sizes of green turtles emerging during the day were significantly smaller than those emerging at night. Hatchlings of both species that emerged from nests during the day had longer emergence durations than those that emerged from nests at night only.Communicated by R.J. Thompson, St. Johns     

Effects of Conversion of Dry Tropical Forest to Agricultural Mosaic on Herpetofaunal Assemblages

Abstract: We explored the impact of forest conversion to agricultural mosaic on anuran, lizard, snake, and turtle assemblages of Neotropical dry forests. Over 2 years, we sampled 6 small watersheds on the west coast of Mexico, 3 conserved and 3 disturbed. The disturbed watersheds were characterized by a mosaic of pastures and cultivated fields (corn, beans, squash) intermingled with patches of different successional stages of dry forest. In each watershed, we conducted 11 diurnal and nocturnal time‐constrained searches in 10 randomly established plots. We considered vulnerability traits of species in relation to habitat modification. Eighteen anuran, 18 lizard, 23 snake, and 3 turtle species were recorded. Thirty‐six species (58%) occurred in both forest conditions, and 14 (22%) and 12 species (19%) occurred only in the conserved and disturbed sites, respectively. Assemblages responded differently to disturbance. Species richness, diversity, and abundance of lizards were higher in disturbed forests. Anuran diversity and species richness were lower in disturbed forest but abundance was similar in both forest conditions. Diversity, richness, and abundance of turtles were lower in disturbed forest. The structure and composition of snake assemblages did not differ between forest conditions. We considered species disturbance sensitive if their abundance was significantly less in disturbed areas. Four anuran (22%), 2 lizard (11%), and 3 turtle (100%) species were sensitive to disturbance. No snake species was sensitive. The decline in abundance of disturbance‐sensitive species was associated with the reduction of forest canopy cover, woody stem cover, roots, and litter‐layer ground cover. Anuran species with small body size and direct embryonic development were especially sensitive to forest disturbance. An important goal for the conservation of herpetofauna should be the determination of species traits associated with extinction or persistence in agricultural mosaics.     

黄芪根瘤菌CA8561和JL84的部分16S rRNA基因序列的测定

报导了黄芪根瘤菌ＣＡ８５６１和ＪＬ８４的部分１６Ｓ ｒＲＮＡ基因序列，测算了它们与已知根瘤菌、茎瘤菌各属模式种之间的遗传距离。结果表明，ＣＡ８５６１和ＪＬ８４均具有独立的进化路线，充分显示了黄芪根瘤菌的遗传多样性。     

Evolutionary Significant Units versus Geopolitical Taxonomy: Molecular Systematics of an Endangered Sea Turtle (genus Chelonia)

Abstract: Taxonomic rank is an important criterion in assessing the conservation priority of an endangered organism: the sole member of a distinct family will generally receive a higher priority than a semi-isolated population in a polytypic species. When cryptic evolutionary partitions are discovered in endangered species, these findings are heralded as a positive step in the conservation process. The opposite action, demoting the taxonomic rank of an endangered organism, can be resisted by the conservation community because it is perceived as detrimental to preservation efforts. We explore the arguments for and against the species status of the endangered black turtle ( Chelonia agassizii ) and contribute an additional data set based on DNA sequences of single-copy nuclear loci. These data are concordant with previous mtDNA surveys in indicating no evolutionary distinction between C. agassizii and adjacent green turtle ( C. mydas ) populations. Although the black turtle is morphologically identifiable at a low level, much of its distinction is based on size and color differences that are highly variable throughout the range of C. mydas . Thus the black turtle would be more accurately classified at the subspecific or population level. There is no strong scientific case available to defend the species status of C. agassizii , and yet that designation has persisted for over a century. We suggest that the maintenance of this name is based on geographical and political considerations, and we propose a pragmatic category for this type of taxonomy: the geopolitical species . Furthermore, we argue against the practice of preserving species status for conservation purposes. There are several good reasons to preserve the black turtle, including morphological diversity and the possibility that it is an incipient evolutionary lineage with novel adaptations; taxonomic rank, however, is not one of them.     

Reef-basel herbivores and the distribution of two seagrasses (Syringodium filiforme and Thalassia testudinum) in the San Blas Islands (Western Caribbean)

Two seagrasses, manatee grass (Syringodium filiforme) and turtle grass (Thalassia testudinum), predominated in the areas bordering Ukkup Tupo, San Blas Islands, Western Caribbean. These seagrasses occupied the following three concentric zones extending outward from the reef: a near-reef turtle grass zone, an intermediate manatee grass zone and an off-reef turtle grass zone. Feeding experiments between January and March 1980 indicate that the absence of manatee grass close to the reef resulted from grazing by reef-associated herbivores, mainly day-active fishes and night-active sea urchins (Diadema antillarum). Grazing on manatee grass by fishes was approximately six times greater than grazing by sea urchins; thus, it appears that herbivorous fishes restrict the near-reef distribution of manatee grass at the study area. Where grazing was heaviest, the inner boundary of the manatee grass zone was farthest from the reef. The volume of manatee grass grazed during experiments was five times the volume of turtle grass consumed, strongly suggesting that the former species is a preferred food item. This is the first evidence for selective grazing on seagrasses.     

Are anthropogenic factors affecting nesting habitat of sea turtles? The case of Kanzul beach,Riviera Maya-Tulum (Mexico)

Marine coast modification and human pressure affects many species, including sea turtles. In order to study nine anthropogenic impacts that might affect nesting selection of females, incubation and hatching survival of loggerhead (Caretta caretta) and green turtle (Chelonia mydas), building structures were identified along a 5.2 km beach in Kanzul (Mexico). A high number of hotels and houses (88; 818 rooms), with an average density of 16.6 buildings per kilometer were found. These buildings form a barrier which prevents reaching the beach from inland, resulting in habitat fragmentation. Main pressures were detected during nesting selection (14.19% of turtle nesting attempts interrupted), and low impact were found during incubation (0.77%) and hatching (4.7%). There were three impacts defined as high: beach furniture that blocks out the movement of hatchlings or females, direct pressure by tourists, and artificial beachfront lighting that can potentially mislead hatchlings or females. High impacted areas showed lowest values in nesting selection and hatching success. Based on our results, we suggest management strategies to need to be implemented to reduce human pressure and to avoid nesting habitat loss of loggerhead and green turtle in Kanzul, Mexico.     

人G—CSF转基因鼠系与正常鼠系比较研究

利用人ＧＣＳＦ基因组基因和ｃＤＮＡ基因作为目的片段,将其受控于２．６ｋｂ的小鼠乳清酸蛋白（ＷＡＰ）基因的调控区下,通过显微注射法获得了两只整合有人ＧＣＳＦ转基因小鼠,通过繁殖建立了稳定的转基因系．一些表型参数测定表明,转基因鼠与正常鼠无明显差别,为对转基因动物进行安全性评价提供了依据