A unique horizontal gene transfer event has provided the octocoral mitochondrial genome with an active mismatch repair gene that has potential for an unusual self-contained function.
A unique horizontal gene transfer event has provided the octocoral mitochondrial genome with an active mismatch repair gene that has potential for an unusual self-contained function.
复制标题
一个独特的水平基因转移事件为八角形的线粒体基因组提供了活跃的不匹配修复基因，该基因具有异常的独立功能。
DOI：
10.1186/1471-2148-11-228
复制
发表时间：
2011-07-29
影响因子：
3.4
通讯作者：
Degnan SM
中科院分区：
文献类型：
--
作者：
Bilewitch JP;Degnan SM
珊瑚虫的线粒体基因组有几个后生动物的非典型特征，包括一个新的基因，被认为在DNA修复中起作用。该mtMutS基因是有利于珊瑚分子系统学，由于其高信息含量。关于mtMutS起源的几个假说已经被提出，并且仍然模棱两可，尽管目前支持的重量是从epsilonproteobacterium或大DNA病毒的水平基因转移。在这里，我们提出了关于mtMutS进化起源的新的和令人信服的证据，并提供了关于其在珊瑚线粒体基因组中的活性、功能能力和稳定性的第一批数据。mtMutS基因具有预期的保守氨基酸、蛋白质结构域和预测的蛋白质三级结构。系统发育分析表明，mtMutS不是MSH家族的成员，因此不是真核生物起源。MtMutS簇与MutS 7谱系的代表密切相关;对这种关系的进一步支持来自共享赋予自包含的错配修复功能的C-末端核酸内切酶结构域。基因表达分析证实，mtMutS是积极转录的珊瑚。线粒体基因的进化率在mtMutS-含有珊瑚是低于他们的hexacoral姐妹组，其中缺乏基因，虽然矛盾的mtMutS基因本身具有较高的突变率比其他珊瑚线粒体基因。珊瑚mtMutS基因是活跃的，编码一种蛋白质，具有DNA错配修复的所有必要成分。较低的线粒体进化速率，以及切口核酸内切酶结构域的存在，都间接支持了珊瑚虫内自给自足的DNA错配修复理论。mtMutS对非真核MutS 7的祖先亲和力为水平基因转移的起源提供了令人信服的支持。直接传播到珊瑚虫的载体可以归因于内共生体中的epsilonproteobacterium或病毒感染，尽管目前还不知道DNA病毒会感染细菌和真核生物，特别是线粒体。在巩固第一个已知的情况下，HGT到动物线粒体基因组，这些发现表明，需要重新考虑的手段，后生动物线粒体基因组的演变。
The mitochondrial genome of the Octocorallia has several characteristics atypical for metazoans, including a novel gene suggested to function in DNA repair. This mtMutS gene is favored for octocoral molecular systematics, due to its high information content. Several hypotheses concerning the origins of mtMutS have been proposed, and remain equivocal, although current weight of support is for a horizontal gene transfer from either an epsilonproteobacterium or a large DNA virus. Here we present new and compelling evidence on the evolutionary origin of mtMutS, and provide the very first data on its activity, functional capacity and stability within the octocoral mitochondrial genome. The mtMutS gene has the expected conserved amino acids, protein domains and predicted tertiary protein structure. Phylogenetic analysis indicates that mtMutS is not a member of the MSH family and therefore not of eukaryotic origin. MtMutS clusters closely with representatives of the MutS7 lineage; further support for this relationship derives from the sharing of a C-terminal endonuclease domain that confers a self-contained mismatch repair function. Gene expression analyses confirm that mtMutS is actively transcribed in octocorals. Rates of mitochondrial gene evolution in mtMutS-containing octocorals are lower than in their hexacoral sister-group, which lacks the gene, although paradoxically the mtMutS gene itself has higher rates of mutation than other octocoral mitochondrial genes. The octocoral mtMutS gene is active and codes for a protein with all the necessary components for DNA mismatch repair. A lower rate of mitochondrial evolution, and the presence of a nicking endonuclease domain, both indirectly support a theory of self-sufficient DNA mismatch repair within the octocoral mitochondrion. The ancestral affinity of mtMutS to non-eukaryotic MutS7 provides compelling support for an origin by horizontal gene transfer. The immediate vector of transmission into octocorals can be attributed to either an epsilonproteobacterium in an endosymbiotic association or to a viral infection, although DNA viruses are not currently known to infect both bacteria and eukaryotes, nor mitochondria in particular. In consolidating the first known case of HGT into an animal mitochondrial genome, these findings suggest the need for reconsideration of the means by which metazoan mitochondrial genomes evolve.
登录
查看更多内容
影响因子：
16
作者：
Junop, MS;Obmolova, G;Yang, W
通讯作者：
Yang, W
影响因子：
3.4
作者：
Claverie, Jean-Michel;Grzela, Renata;Abergel, Chantal
通讯作者：
Abergel, Chantal
影响因子：
3
作者：
Li, L;Kato, C;Horikoshi, K
通讯作者：
Horikoshi, K
影响因子：
13.8
作者：
Malik, HS;Henikoff, S
通讯作者：
Henikoff, S
影响因子：
3.9
作者：
Brugler, Mercer R.;France, Scott C.
通讯作者：
France, Scott C.