锥形蜗牛,作为一种海洋生物,具有丰富的物种多样性。传统上,锥蜗牛的分类主要基于雷达,shell,和解剖学特征。由于这些表型特征\'高人口变异性和局部适应和趋同的倾向,识别物种可能很困难,有时也不准确。此外,线粒体基因组包含高度的系统发育信息,因此,完整的有丝分裂基因组越来越多地用于推断分子系统发育。为了丰富锥蜗牛(Caenogastropoda:Conidae)的有丝分裂基因组数据库,四种Conus物种的有丝分裂原,即,C.帝国主义(15,505bp),C.文学(15,569bp),C.处女座(15,594bp),和C.marmoreus(15,579bp),进行了表征和比较。所有4个有丝分裂基因组包括13个蛋白质编码基因,2核糖体RNA基因,22个tRNA基因,和非编码区域。两个新测序的有丝分裂基因组的所有蛋白质密码子基因(PCG)使用TAA或TAG作为末端密码子。大多数PCG使用传统的起始密码子ATG,但是在C.imperalis的基因(NADH脱氢酶亚基4(nad4))中检测到另一个起始密码子GTG。此外,在PCGs的基础上,重建了20个Conus物种之间的系统发育关系,COX1和使用贝叶斯推断(BI)和最大似然(ML)的完整有丝分裂体。系统发育结果支持C.litteratus,C.quercinus,和C.virgo聚集在一起作为姐妹组(PP=1,BS=99),但是他们不支持C.imperialis和C.tribblei的系统发育关系(PP=0.79,BS=50)。此外,我们的研究确定PCGs和完整的有丝分裂基因组是Conus物种系统发育推断的两个有用标记。这些结果丰富了南海锥螺线粒体的资料,为基于线粒体基因组的锥螺系统发育关系的解释提供了可靠的依据。
Cone snails, as a type of marine organism, have rich species diversity. Traditionally, classifications of cone snails were based mostly on radula, shell, and anatomical characters. Because of these phenotypic features\' high population variability and propensity for local adaptation and convergence, identifying species can be difficult and occasionally inaccurate. In addition, mitochondrial genomes contain high phylogenetic information, so complete mitogenomes have been increasingly employed for inferring molecular phylogeny. To enrich the mitogenomic database of cone snails (Caenogastropoda: Conidae), mitogenomes of four Conus species, i.e., C. imperialis (15,505 bp), C. literatus (15,569 bp), C. virgo (15,594 bp), and C. marmoreus (15,579 bp), were characterized and compared. All 4 of these mitogenomes included 13 protein-coding genes, 2 ribosomal RNA genes, 22 tRNA genes, and non-coding regions. All the Protein Codon Genes (PCGs) of both newly sequenced mitogenomes used TAA or TAG as a terminal codon. Most PCGs used conventional start codon ATG, but an alternative initiation codon GTG was detected in a gene (NADH dehydrogenase subunit 4 (nad4)) of C. imperialis. In addition, the phylogenetic relationships were reconstructed among 20 Conus species on the basis of PCGs,
COX1, and the complete mitogenome using both Bayesian Inference (BI) and Maximum Likelihood (ML). The phylogenetic results supported that C. litteratus, C. quercinus, and C. virgo were clustered together as a sister group (PP = 1, BS = 99), but they did not support the phylogenetic relation of C. imperialis and C. tribblei (PP = 0.79, BS = 50). In addition, our study established that PCGs and complete mitogenome are the two useful markers for phylogenetic inference of Conus species. These results enriched the data of the cone snail\'s mitochondrion in the South
China Sea and provided a reliable basis for the interpretation of the phylogenetic relationship of the cone snail based on the mitochondrial genome.