The Multipartite Mitochondrial Genome of Liposcelis bostrychophila: Insights into the Evolution of Mitochondrial Genomes in Bilateral Animals
The Multipartite Mitochondrial Genome of Liposcelis bostrychophila: Insights into the Evolution of Mitochondrial Genomes in Bilateral Animals
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Liposcelis bostrychophila 的多部分线粒体基因组：深入了解双边动物线粒体基因组的进化
DOI：
10.1371/journal.pone.0033973
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发表时间：
2012-03-30
期刊：
影响因子：
3.7
通讯作者：
Wang, Jin-Jun
中科院分区：
文献类型：
--
作者：
Wei, Dan-Dan;Shao, Renfu;Wang, Jin-Jun
书虱是世界范围内储粮的主要害虫，与寄生虱目有密切关系。我们对嗜酸脂胞杆菌线粒体(Mt)基因组进行了测序，发现典型的双侧动物的单条Mt染色体已经断裂成两条中等大小的染色体并被替换，每条染色体大约含有双侧动物典型Mt染色体的一半的基因。这些mt染色体的大小分别为8,530 bp(mt染色体I)和7,933 bp(mt染色体II)。有趣的是，mt染色体I的丰度是染色体II的两倍。当小mt染色体与典型的大mt染色体共存时，两侧动物对紧凑mt基因组的选择压力似乎有利于小mt染色体。因此，在双侧动物中，小的mt染色体可能比大的mt染色体具有选择优势。对Psocodea属(Pocoptera+PhthiRaptera)mt基因组序列的系统发育分析表明：1)Pocoptera目(书虱和蜡虱)是寄生性的；2)PhthiRaptera目(寄生虱目)是单系进化。然而，在寄生虱子中，Ischnocera亚目是寄生的；这不同于传统观点，即寄生虱子的每个亚目都是单系的。
Booklice (order Psocoptera) in the genus Liposcelis are major pests to stored grains worldwide and are closely related to parasitic lice (order Phthiraptera). We sequenced the mitochondrial (mt) genome of Liposcelis bostrychophila and found that the typical single mt chromosome of bilateral animals has fragmented into and been replaced by two medium-sized chromosomes in this booklouse; each of these chromosomes has about half of the genes of the typical mt chromosome of bilateral animals. These mt chromosomes are 8,530 bp (mt chromosome I) and 7,933 bp (mt chromosome II) in size. Intriguingly, mt chromosome I is twice as abundant as chromosome II. It appears that the selection pressure for compact mt genomes in bilateral animals favors small mt chromosomes when small mt chromosomes co-exist with the typical large mt chromosomes. Thus, small mt chromosomes may have selective advantages over large mt chromosomes in bilateral animals. Phylogenetic analyses of mt genome sequences of Psocodea (i.e. Psocoptera plus Phthiraptera) indicate that: 1) the order Psocoptera (booklice and barklice) is paraphyletic; and 2) the order Phthiraptera (the parasitic lice) is monophyletic. Within parasitic lice, however, the suborder Ischnocera is paraphyletic; this differs from the traditional view that each suborder of parasitic lice is monophyletic.