颈链血苔虫线粒体基因组的测定及其系统发育学意义

The complete mitochondrial genome of Watersipora subtorquata and its phylogenetic significance

本研究测定了颈链血苔虫的线粒体基因组。它是一个双链闭合环状分子,全长14144bp,与其他后生动物相比相对较小;颈链血苔虫线粒体基因组所有的基因都编码在同一条链上。相比其他后生动物它具有独特的基因排列顺序,而且与已发表的两个苔藓动物线粒体基因组相比,基因排列顺序也显著不同,这说明苔藓动物线粒体基因组经历了大规模的基因重排过程。基因排列顺序比较分析的结果支持苔藓动物为原口动物的观点,提示我们基因排列顺序的比较分析可能会成为苔藓动物门进化地位确定的良好途径。

Bryozoans are small sessile aquatic colonial animals, and their phylogenetic position has been controversial for long time. In this paper, we have determined the complete mi- tochondrial genome of Watersipora subtorquata. It is a circular molecule of 14 144 bp, relative- ly small compared with most other published metazoan mitochondrial genomes. It is unusual that all genes are transcribed from the same strand. The gene order is unique compared with mtDNA of other metazoans, and drastic rearrangement was also found when compared with mtDNA of the other two bryozoans. It indicates that drastic rearrangement has happened in the mitochondrial genome of bryozoans. Comparison of gene order supports the protostome affinity of Bryozoa, and indicates that comparison of gene order may be especially useful for the establishment of the phylogenetic position of Bryozoa. This study provides important bryozoan molecular data which will facilitate the phylogenetic research of Bryozoa.