Museo Nacional de Ciencias Naturales (MNCN-CSIC), José Gutiérrez Abascal 2, 28006 Madrid, Spain.
Gene. 2014 Sep 1;547(2):257-66. doi: 10.1016/j.gene.2014.06.040. Epub 2014 Jun 23.
The complete nucleotide sequence of the mitochondrial (mt) genome of the deep-sea vent snail Ifremeria nautilei (Gastropoda: Abyssochrysoidea) was determined. The double stranded circular molecule is 15,664 pb in length and encodes for the typical 37 metazoan mitochondrial genes. The gene arrangement of the Ifremeria mt genome is most similar to genome organization of caenogastropods and differs only on the relative position of the trnW gene. The deduced amino acid sequences of the mt protein coding genes of Ifremeria mt genome were aligned with orthologous sequences from representatives of the main lineages of gastropods and phylogenetic relationships were inferred. The reconstructed phylogeny supports that Ifremeria belongs to Caenogastropoda and that it is closely related to hypsogastropod superfamilies. Results were compared with a reconstructed nuclear-based phylogeny. Moreover, a relaxed molecular-clock timetree calibrated with fossils dated the divergence of Abyssochrysoidea in the Late Jurassic-Early Cretaceous indicating a relatively modern colonization of deep-sea environments by these snails.
深海喷口蜗牛 Ifremeria nautilei（腹足纲：深脐目）的线粒体（mt）基因组的完整核苷酸序列已被确定。该双链环状分子长 15664 个碱基对，编码典型的 37 种后生动物线粒体基因。Ifremeria mt 基因组的基因排列与头足类动物的基因组组织最为相似，仅在 trnW 基因的相对位置上有所不同。Ifremeria mt 基因组 mt 蛋白编码基因的推导氨基酸序列与腹足纲主要谱系的同源序列进行了比对，并推断了系统发育关系。重建的系统发育支持 Ifremeria 属于腹足纲，并且与后鳃亚纲超科密切相关。结果与重建的基于核的系统发育进行了比较。此外，利用化石标定的松弛分子钟时间树表明，深海环境中这些蜗牛的分化发生在侏罗纪晚期至白垩纪早期，表明它们是相对较新的深海环境殖民者。
