Bandyopadhyay Pradip K, Stevenson Bradford J, Cady Matthew T, Olivera Baldomero M, Wolstenholme David R
Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112, USA.
Toxicon. 2006 Jul;48(1):29-43. doi: 10.1016/j.toxicon.2006.04.013. Epub 2006 May 5.
We have determined the first complete nucleotide sequence of the mitochondrial genome of a venomous mollusc, the Conoidean gastropod, Lophiotoma (Xenuroturris) cerithiformis. It is 15,380 nucleotide pairs (ntp) and encodes 13 proteins, two ribosomal RNAs and 22 tRNAs of the mitochondrion's own protein synthesizing system. The protein mRNAs, ribosomal RNAs and 13 of the tRNAs are transcribed from the same strand, the remaining tRNAs from the other strand. The longest segment of unassigned sequence is 139 ntp and includes a 82 ntp segment that is a perfect inverted repeat sequence of 37 ntp separated by 8 nt. The gene arrangement of L. cerithiformis mtDNA shows remarkable similarity to the gene arrangements of mtDNAs of the vetigastropod Haliotis rubra, the polyplacophoran Katharina tunicata and the cephalopod Octopus vulgaris, but differs dramatically from the gene arrangements found in the mtDNAs of pulmonate and opisthobranch gastropods, as well as mtDNAs of bivalves and scaphopods. A single sixteen gene inversion that distinguishes L. cerithiformis mtDNA from mtDNAs of H. rubra, K. tunicata and O. vulgaris is shared by mtDNA of a littorinomorph gastropod Littorina saxitalis, suggesting a close relationship of conoidean and littorinomorph gastropods.
我们已经确定了一种有毒软体动物——芋螺超科腹足纲动物Lophiotoma（Xenuroturris）cerithiformis线粒体基因组的首个完整核苷酸序列。该序列有15380个核苷酸对（ntp），编码13种蛋白质、两个核糖体RNA以及线粒体自身蛋白质合成系统的22种转运RNA。蛋白质信使RNA、核糖体RNA以及13种转运RNA转录自同一条链，其余转运RNA转录自另一条链。未确定序列的最长片段为139个ntp，其中包括一个82个ntp的片段，该片段是由8个nt分隔的37个nt的完美反向重复序列。L. cerithiformis线粒体DNA的基因排列与蝾螺超科的红鲍、石鳖Katharina tunicata以及头足纲的普通章鱼的线粒体DNA基因排列显示出显著的相似性，但与肺螺亚纲和后鳃亚纲腹足纲动物的线粒体DNA以及双壳纲和掘足纲动物的线粒体DNA中发现的基因排列有很大差异。一个将L. cerithiformis线粒体DNA与红鲍、Katharina tunicata和普通章鱼的线粒体DNA区分开来的单十六基因倒位，被滨螺科腹足纲动物Littorina saxitalis的线粒体DNA所共有，这表明芋螺超科和滨螺科腹足纲动物关系密切。
