中文摘要：

蜱螨亚纲包括蜱类和螨类,是节肢动物中物种多样性最高的类群之一。本文综述了当前已测序的28种蜱螨线粒体基因组的研究成果。概括起来,蜱螨线粒体基因组具有以下特点：（1）大小变异显著,其中柑橘全爪螨Panonychuscitri线粒体基因组在目前已测节肢动物中最小（13077bp）;（2）一般碱基组成偏向A和T,但6种蜱螨具有相反的GC-偏斜（正值）;（3）基因组的碱基组成及A＋T富集区的位置、长度和拷贝数等变异显著,其中4种叶螨的A＋T含量最高,其A＋T富集区在目前已测节肢动物中最短（44～57bp）;（4）基因高度重排,特别是真螨总目的种类,但重排与高分类阶元无相关性;（5）真螨总目部分螨类的tRNA基因极度缩短,不能形成经典的三叶草二级结构。作者建议要进一步测定更多蜱螨的线粒体基因组,验证蜱螨非典型tRNA基因的生物学功能性,分析蜱螨线粒体基因组的分子进化机制,开展蜱螨线粒体转录组研究等。

英文摘要：

Acari,including ticks and mites,is one of the most diverse group of arthropods.In this paper,we reviewed the research progress in the 28 sequenced complete mitochondrial genomes of acari species.These mitochondrial genomes have several marked features：（1） There is significant variation in the size of mitochondrial genomes among the 28 acari species,and the mitochondrial genome of Panonychus citri（13 077 bp） is the smallest among all sequenced arthropods;（2） The base composition of all acari mitochondrial genomes are biased toward A and T,with six species harboring reverse GC-skew values（positive value）;（3） The base composition and the position,length,copy number of the A＋T-rich regions vary greatly among the 28 acari species,of which four tetranychid species harbor the highest A＋T content within acari and the shortest A＋T-rich region（44-57 bp） among arthropods;（4） High gene rearrangements are found in acari mitochondrial genomes,especially in those of Acariformes,but the rearrangements are not correlated to high taxonomic ranks;（5） The tRNA genes in some species of Acariformes are extremely truncated,presenting atypical cloverleaf structures.We suggest that it is necessary to sequence more acari mitochondrial genomes aiming to investigate whether these tRNA genes lacking both D-and T-arms are functional or not,to analyze the molecular mechanisms of evolution in acari mitochondrial genomes,and to carry out the acari mitochondrial transcriptome studies.