Phylogeny of Limenitidinae Butterflies （Lepidoptera： Nymphalidae） Inferred from Mitochondrial Cytochrome Oxidase I Gene Sequences

The phylogenetic analyses of the subfamily Limenitidinae are performed based on 1471 bp of mtDNA cytochrome oxidase subunit I (C01) gene sequence data which were obtained from 21 individuals spanning 9 genera, along with those of 17species obtained from GenBank, using Apatura iris, Aglais urticae, and Polyura dolon as outgroup species. Although the transitions at the third codon positions of the COI data set were highly saturated, they were still retained for analysis as they contain the majority of the phylogenetic information, and thus, the maximum pasimony (MP) under different weighting schemes and maximum likelihood (ML) trees were reconstructed in this study. The results showed that within this subfamily, the results based on the COI gene sequences are approximately identical to the traditional classification results. However, the clustering of Lexias pardalis and Tanaecia julii within the genus Euthalia as well as the clustering of Phaedyma aspasia within the genus Neptis with weak support are different from that of the current classification scheme made by Chinese scholars. The genus Limenitis is splited into two subelusters in the trees constructed by using MP and ML methods. These results support one of the strongest hypotheses for the tribe relationships within Limenitidinae.     

还少丹对D-半乳糖衰老模型小鼠心肌线粒体DNA缺失的影响

目的探讨还少丹对D-半乳糖(D-gal)诱导的衰老小鼠心肌线粒体DNA(mtDNA)缺失的影响。方法将40只小鼠随机分为空白对照组、衰老模型组、还少丹低、高剂量组,用D-半乳糖建立衰老模型,分别给予蒸馏水和还少丹水煎液灌胃。连续给药6周后,采用聚合酶链反应(PCR)技术扩增心肌组织mtDNA,经琼脂糖凝胶电泳检测扩增条带,用光密度扫描定量各组mtDNA的缺失率。结果空白对照组未见mtDNA缺失型扩增条带,其余各组均出现不同程度的缺失型扩增条带;与模型组比较,低、高剂量组小鼠心肌mtDNA缺失率明显降低,差异均具有统计学意义(P<0.05);而低剂量与高剂量组之间比较mtDNA的缺失率差异无统计学意义(P>0.05)。结论还少丹能减少D-半乳糖诱导的衰老小鼠心肌mtDNA的缺失程度,提示该方能降低mtDNA的氧化损伤,保护mtDNA的结构完整性,从分子水平上为还少丹抗衰老的作用机制提供了一定的实验依据。 更多还原     

线粒体基因与疾病关系的研究进展

以线粒体结构和功能缺陷为主要病因的疾病常称为线粒体病,主要指线粒体基因变化所致的疾病。mtDNA基因表达受众多因素调控,存在多个突变位点,其发生突变的概率很大。基因突变和基因表达异常可影响细胞对氧的利用,与一系列病理生理过程密切相关,故而mtDNA被认为与疾病的发生有密切关系。文章主要对近年来线粒体所致疾病与mtDNA相关变化的研究进展作一综述。     

基于mtDNA COI的假眼小绿叶蝉系统发育研究

克隆测定了12个茶树假眼小绿叶蝉Empoasca vitis（Göthe）种群84个样本和5个叶蝉近缘种外群62个虫体的线粒体DNA COI基因序列片段,利用生物信息学软件分析其序列同源性、遗传结构及系统进化关系。发现我国茶树假眼小绿叶蝉种群间的遗传距离为0.5%~1.2%,远小于昆虫物种2%的界限,未呈现明显遗传分化,ML分子系统树也显示其种群个体呈平行分布。假眼小绿叶蝉与几种外群叶蝉的遗传距离在14.8%~24.5%之间,依次为葡萄小绿叶蝉<葡萄二星叶蝉<桃一点斑叶蝉,说明它与葡萄小绿叶蝉亲缘关系最近,与系统进化树的聚类结果一致。本研究首次通过mtCOI基因序列分析,揭示了假眼小绿叶蝉遗传结构及它与近缘种叶蝉的系统进化关系,为解释它在茶园的起源及适应机制提供了基础。     

基于线粒体控制区的许氏平鲉养殖群体与野生群体比较研究

为研究许氏平鲉养殖群体与野生群体遗传结构及遗传多样性状况,采用PCR扩增获得许氏平鲉线粒体DNA控制区高变区片段,并对其进行比对分析。结果显示,在长度为451 bp的线粒体控制区片段中,养殖群体单倍型多样度(0.540±0.067~0.815±0.021)明显低于野生群体(0.883±0.053~0.944±0.028),而核苷酸多样度(0.001±0.001~0.007±0.004)与野生群体(0.004±0.003~0.007±0.004)相差不大,遗传多样性水平均较低。在52个单倍型中,养殖群体仅占12个,且有6个单倍型与野生群体共享。群体间遗传分化指数和AMOVA分析结果显示,养殖群体和野生群体之间以及养殖群体之间的遗传分化较大,而野生群体间遗传变异较小,组群间的遗传分化较小且不显著(ΦCT=-0.013;P0.05)。单倍型最小跨度树和NJ系统发育树均未检测到明显的谱系结构。     

5种仓储豆象的分子鉴定和检测

本研究以在检疫中经常被截获的5种豆象为研究对象,通过对GenBank中5种豆象mtDNA COⅠ序列的查询,并进行序列比对,共设计了30对引物,通过筛选获得5对能分别鉴定5种豆象的特异引物,并用50、25、10、5、1、0.5、0.1、0.05ng/μL 8个不同浓度系列的豆象DNA模板来检测灵敏度,结果表明,豌豆象和四纹豆象特异引物对的灵敏度为0.1ng/μL,蚕豆象、菜豆象和绿豆象特异引物对的灵敏度为0.5ng/μL。该方法可用于快速准确地鉴定5种豆象,对于豆象类害虫的检测监测具有重要意义。     

Genetic diversity within two Tunisian wild jirds: Meriones shawi and Meriones libycus (Rodentia,Gerbillinae)

Three Meriones species inhabit Tunisia, namely M. shawi, M. libycus and M. crassus, but little genetic data exist on these gerbils. We collected Meriones from eight localities in Tunisia, and obtained mitochondrial (cytochrome b) and nuclear (IRBP) gene sequence data for 37 and 13 specimens, respectively, belonging to two species: M. shawi and M. libycus. We also optimised three microsatellite markers previously described in M. unguiculatus to obtain a finer analysis of their genetic diversity and geographic structure, given their wide distribution. Phylogenetic inferences of cyt b and IRBP data for these species, in the context of other gerbillin data, corroborate their taxonomic affinities reported by previous studies. High cyt b haplotype diversity was observed in both species (25 haplotypes in 29 and 27 sequences for M. shawi and M. libycus, respectively) with little geographical structure for M. shawi but three divergent groups in M. libycus. The average microsatellite diversity within each population was high (H_O ≥ 0.6, H_E ≥ 0.8) with M. libycus populations attaining the highest values. Population differentiation was moderate for several population pairs (F_st ≥ 0.1), the highest being between M. shawi populations. However, genetic distance among populations was not significantly correlated with geographic distance in either M. shawi or M. libycus. Our results contribute to a better characterisation of Tunisian Meriones species, suggesting high geographic structure in mtDNA of M. libycus populations within North Africa.     

略阳乌鸡线粒体DNA控制区(D-loop)的遗传多样性分析

为了研究略阳乌鸡线粒体DNA控制区（mtDNA D-loop）的遗传多样性和起源,本研究对30只略阳乌鸡样品的mtDNA D-loop全序列进行了PCR扩增和测序,结合GenBank中公布的其他鸡的D-loop区序列,分析略阳乌鸡线粒体多态性及其起源。结果表明,略阳乌鸡mtDNA D-loop区全序列中,A、C、G、T平均含量分别为26.6%、26.6%、13.4%和33.4%,26个核苷酸多态位点均为转换位点,核苷酸多样度（Pi）为0.00705,单倍型变异度（Hd）为1.000,中性检验Tajima's D值为-0.47272。通过群体构建的系统进化树发现,略阳乌鸡样品在系统进化树上聚为4大分支。研究结果表明,略阳乌鸡群体内个体序列变异程度较大,遗传多样性丰富,揭示略阳乌鸡在遗传组成上具有4个母系来源。     

在北京和河北局部地区Q型烟粉虱取代了B型烟粉虱

利用烟粉虱[Bemisia tabaci(Gennadius)]B生物型和Q生物型mtDNA COⅠ基因片段的特异性引物及烟粉虱mtDNA COⅠ基因片段通用引物,对2009年采自北京市海淀区、昌平区和河北廊坊市的蔬菜所3个基地的烟粉虱种群的生物型进行了鉴定,同时以本实验室在温室内长期饲养的B型烟粉虱种群作为对照。结果表明,2009年在3个地区所采集的烟粉虱全部为Q型,而在2004年这3个基地发生为害的烟粉虱全部为B型,表明Q型烟粉虱已经取代了B型烟粉虱在这些地区发生为害。     

西北马鹿群体遗传多样性及系统地位

【目的】揭示西北马鹿(Cervus elaphus)群体的遗传多样性及系统地位,为科学地保护和利用我国西北地区马鹿资源提供基础研究材料。【方法】对塔里木马鹿、阿尔泰马鹿、天山马鹿、甘肃马鹿及阿拉善马鹿5个群体108个个体的D-loop全序列进行扩增、测序,分析其碱基组成及变异,构建系统发育树,研究西北马鹿群体遗传结构、群体遗传多样性及其系统地位。【结果】共检测到40个单倍型,平均单倍型多样度(Hd)为0.998±0.006,平均核苷酸多样度(Pi)为0.041±0.005,平均核苷酸差异数(K)为36.08。构建NJ和MP分子系统发育树发现,塔里木马鹿与其他马鹿遗传距离较远,分属于不同的类群;阿尔泰马鹿、天山马鹿及甘肃马鹿之间均存在基因交流,可能是群体间引种杂交所致。【结论】西北地区马鹿整体遗传多样性丰富;中国马鹿可能起源于欧洲;部分马鹿群体间存在基因交流情况。