白蚁mtDNA提取方法改良及检测

利用mtDNA多态性进行种类鉴定是一种分子生物学常用方法,从DNA水平对白蚁进行物种鉴别并探讨物种的进化,其必要前提是提取到一定数量和质量的mtDNA．在分离得到线粒体后,分别采用CTAB、SDS2种方法提取mtDNA．紫外分光光度计检~I]DNA纯度及浓度,用mtDNA特异性引物进行PCR扩增检测．试验证明2种方法均能成功提取白蚁的mtDNA,SDS法提取效果较好．     

Molecular biological analysis of remains from Jiangjungou Cemetery in Inner Mongolia

The 364-bp nucleotide sequence in hypervariable region I (HVRI) of mitochondrial DNA is successfully amplified from 9 out of 11 individuals of an ancient population buried in the Jiangjungou Cemetery in Inner Mongolia dated back to the Warring States Period in China. Nine fragments with different variations are obtained. A phylogenetic tree and a multidimensional scaling (MDS) plot are constructed using mtDNA sequences from the ancient population and several modern Asian populations. The results show that ancient population shares a closer genetic relationship with East Asian populations than with North and Central Asian populations. The genetic and historical evidence raise the possibility that the population might be the immigrants from Zhongyuan area, sent by the King Wuling of Zhao State to guard the nation against the attack from Huns.     

内蒙古和林格尔东周时期古代人群的分子遗传学分析

对10个古代个体的线粒体DNA高可变Ⅰ区进行了扩增和测序. 基于和林格尔古代人群与现今相关欧亚人群的mtDNA序列， 进行了系统发育分析和多维尺度分析. 研究结果表明, 和林格尔古代人群在母系遗传上与现在北亚人群的亲缘关系最近. 结合考古学、 人类学以及分子生物学的研究， 推断这个古代人群是从蒙古高原以及外贝加尔地区南下迁移至今天的内蒙古和林格尔地区的游牧人.     

GENETIC DIVERSITY AMONG CHINESE SIKA DEER (CERVUS NIPPON) POPULATIONS AND RELATIONSHIPS BETWEEN CHINESE AND JAPANESE SIKA DEER

SIKA DEER,CERVUS NIPPON,WAS HISTORICALLY WIDE-SPREAD THROUGHOUT NORTHEASTERN ASIA,FROM THE USSURI REGION TO VIETNAM,INCLUDING THE KOREAN PENINSULA,MAINLAND CHINA AND TAIWAN,AND THE JAPANESE ARCHI-PELAGO,AND UP TO13SUBSPECIES HAVE BEEN DESCRIBED[1].THE FOS…     

绿头鸭mtDNA限制性内切酶酶切分析

采用碱变性法制备绿头鸭肝细胞ｍｔＤＮＡ，经纯化后测其分子量为１６．７ｋｂ．用限制性内切酶进行酶切分析，结果表明ＢａｍＨⅠ、ｐｓｔⅠ和ＨｉｎｄⅢ在绿卖鸭ｎｔＤＮＡ分子上分别有４个、２个和３个酶切位点。与由番鸭、北京鸭和建昌鸭肝细胞ｍｔＤＮＡ为材料所得的研究结果比较，发现绿头鸭与番鸭及家鸭在ｍｔＤＮＡ种质方面存在着高度差异。     

Can the occurrence of rare insertion／deletion polymor—phisms in human mtDNA be verfied from phylogeny？

Due to its specific characteristics,such as ma-ternal inheritance and absence of recombination,each mtDNA belongs to certain monophyletic clade in the rooted mtDNA tree(haplogroup) according to the mutations it har-bors,Rare mutation(excluding parallel mutation) occurring at multiple times in different haplogroups could thus be a potential reading error according to the mtDNA phylogent.This experience has been widely used im double-checking the credibility of the rare mutations in human mtDNA sequences.However,no test has been performed so far for the feasibility of applying this strategy to the rare insertion/deletion(indel) events in mtDNA sequences.In this study,we attempted to relate the rare indels in mtDNAs to their haplogroup status in a total of 2352 individuals from 50 populations in China.Our results show that the insertion of A at position 16259 is restricted to a subclade of haplogroup Cand can be verified.The other indel polymorphisms,Which occur in the repeat of the deleted or inserted nucleotide(s),may not be distin-guished from phantom mutations from a phylogenetic point of view.Independently and multiply sequencing the frag-ment with the indel is the best and the most reliable way for confirmation.     

丰鲤及其双亲线粒体DNA限制性酶切图谱的研究

采用密度梯度离心及RNase消化法制备并纯化了丰鲤(Fengcarp)、兴国红鲤(Xingguoredcarp)及散鳞镜鲤(Scatterscaledmirrorcarp)的肝脏线粒体DNA,用10种限制性内切酶HindIII、EcoRI、BamHI、XbaI、XhoI、PstI、BglII、SalI、BglI、PvuII进行了分析.丰鲤mtDNA相对分子质量约为9 88×106,大小约为16 49kb;兴国红鲤mtDNA相对分子质量约为9 89×106,大小约为16 50kb;散鳞镜鲤mtDNA相对分子质量约为9 87×106,大小为16 48kb.HindIII、EcoRI、BglI、BamHI、XbaI、XhoI、SalI、BglII、PstI及PvuII在丰鲤、兴国红鲤、散鳞镜鲤线粒体DNA分子上均分别有6、4、3、3、3、1、1、0、1和4个切点.根据单酶切及双酶切结果,构建了丰鲤、兴国红鲤、散鳞镜鲤mtDNA9种酶的限制性酶切图谱,结果表明丰鲤、兴国红鲤及散鳞镜鲤mtDNA间缺乏变异性.     

Sequencing and analysis of the complete mitochondrial DNA of Russell＇s snapper （L. russellii）

The entire mitochondrial DNA sequence （mitogenome） of Russell＇s snapper （Lutjanus russellii） was determined using long PCR and primer-walking methodology, representing the first complete mitogenome accessioned for Lutjanid fishes （16,505 bp, GenBank Accession No. EF514208）. The mitogenome was similar in gene composition and order to those of other vertebrates, having 37 structural genes, i.e., two ribosomal RNAs, 22 transfer RNAs, and 13 protein-coding genes. Phylogenetic analyses based on the mtDNA sequence of Russell＇s snapper supported a close relationship between Lutjaninae and Caesioninae, consistent with taxonomic hypotheses based on morphology. More studies utilizing mitogenomes are needed to resolve high-level relationships among snappers.     

The Influence of 5′,8-Cyclo-2′-deoxypurines on the Mitochondrial Repair of Clustered DNA Damage in Xrs5 Cells: The Preliminary Study

The 5′,8-cyclo-2′-deoxypurines (cdPus) affect the DNA structure. When these bulky structures are a part of clustered DNA lesions (CDL), they affect the repair of the other lesions within the cluster. Mitochondria are crucial for cell survival and have their own genome, hence, are highly interesting in the context of CDL repair. However, no studies are exploring this topic. Here, the initial stages of mitochondrial base excision repair (mtBER) were considered—the strand incision and elongation. The repair of a single lesion (apurinic site (AP site)) accompanying the cdPu within the double-stranded CDL has been investigated for the first time. The type of cdPu, its diastereomeric form, and the interlesion distance were taken into consideration. For these studies, the established experimental model of short oligonucleotides (containing AP sites located ≤7 base pairs to the cdPu in both directions) and mitochondrial extracts of the xrs5 cells were used. The obtained results have shown that the presence of cdPus influenced the processing of an AP site within the CDL. Levels of strand incision and elongation were higher for oligos containing RcdA and ScdG than for those with ScdA and RcdG. Investigated stages of mtBER were more efficient for DNA containing AP sites located on 5′-end side of cdPu than on its 3′-end side. In conclusion, the presence of cdPus in mtDNA structure may affect mtBER (processing the second mutagenic lesion within the CDL). As impaired repair processes may lead to serious biological consequences, further studies concerning the mitochondrial repair of CDL are highly demanded.     

淡水鱼类线粒体DNA D-loop基因的引物设计和应用

 线粒体DNA测序已广泛应用于鉴定和区分种类以及解决系统进化关系问题。本文选取已测定的主要淡水鱼类的线粒体DNA D-loop基因序列进行同源性比较,寻找保守序列,利用简并性原则设计一对通用的简并引物。利用设计的引物对广东省珠江流域主要的淡水鱼类线粒体DNA D-loop控制区基因进行扩增,均能获得单一的目的DNA片断,特异性扩增产物大小为1 kb左右。经测序及与GenBank同源序列的比较,证实为包含线粒体控制区全序列的扩增产物。本研究所设计的引物和应用的方法可以快速地同时对多种鱼类进行大规模的遗传背景分析,鉴定某些难于鉴别的近缘物种,为我国鱼类的种类鉴定、地理种群鉴别及种质资源的评估提供重要的工具。