根据取自两种贻贝(Arcuatulasenhousia和Mytiluscoruscus)的标本的线粒体基因组(有丝分裂基因组)的核苷酸序列,通过基因组学的复杂方法进行了调查,分子系统发育学,和进化遗传学。研究的贻贝的有丝分裂体结构,像许多其他无脊椎动物一样,似乎比脊椎动物更具可变性,包括改变基因顺序,重复,和删除,tRNA基因最常见;贻贝物种的有丝分裂基因组也有可变的大小。结果证明了蛋白质多肽的一些非常重要的特性,如疏水性及其通过嘌呤和嘧啶核苷酸比例测定。这一事实可能间接表明纯化自然选择以支持多肽功能性的必要性。然而,根据自然界中生物的自然截止选择的广泛接受和合乎逻辑的概念,这解释了它对抗非同义密码子(突变)中有害核苷酸取代的作用,以及它在群体中保持多肽的活性(有效)大分子,在目前的论文中,我们无法得到支持这一概念的明确证据。这里,研究了来自双壳软体动物最大分类群之一的贻贝物种的系统发育和系统学,被称为Mytilidae的家族。Mytilidae(Mytilida目)的系统发育,目前在系统学方面没有共识,使用26-27个有丝分裂基因组的数据矩阵重建。最初,下载来自GenBank的一组100个序列,并检查它们的性别:它们的起源是女性(F)还是男性(M)。我们对新数据的分析证实了贻贝中F/M有丝分裂细胞系之间已知的巨大差异。使用组合的遗传标记集进行F系的系统发育重建,仅重建蛋白质编码基因(PCGs),只有rRNA+tRNA基因,和所有的基因。此外,分析包括使用由其他数据矩阵组成的核苷酸序列,如20-68个有丝分裂基因组序列。与MRCA背离的时间,通过BEAST2估计,Mytilidae接近293Mya,表明它们起源于志留纪时期。从这些数据来看,建议对Mytillinae亚科及其系统学的系统发育达成共识。特别是,关于贻贝系统学的长期争论得到了解决,和Mytilinae的亚科,是单系的。拓扑信号,这在本文和文献中得到了强烈的解决,驳斥了关于Mytilinae单系的理论。
Based on the nucleotide sequences of the mitochondrial genome (mitogenome) of specimens taken from two mussel species (Arcuatula senhousia and Mytilus coruscus), an investigation was performed by means of the complex approaches of the genomics, molecular phylogenetics, and evolutionary genetics. The mitogenome structure of studied mussels, like in many other invertebrates, appears to be much more variable than in vertebrates and includes changing gene order, duplications, and deletions, which were most frequent for tRNA genes; the mussel species\' mitogenomes also have variable sizes. The results demonstrate some of the very important properties of protein polypeptides, such as hydrophobicity and its determination by the purine and pyrimidine nucleotide ratio. This fact might indirectly indicate the necessity of purifying natural selection for the support of polypeptide functionality. However, in accordance with the widely accepted and logical concept of natural cutoff selection for organisms living in nature, which explains its action against deleterious nucleotide substitutions in the nonsynonymous codons (mutations) and its holding of the active (effective) macromolecules of the polypeptides in a population, we were unable to get unambiguous evidence in favor of this concept in the current paper. Here, the phylogeny and systematics of mussel species from one of the largest taxons of bivalve mollusks are studied, the family known as Mytilidae. The phylogeny for Mytilidae (order Mytilida), which currently has no consensus in terms of systematics, is reconstructed using a data matrix of 26-27 mitogenomes. Initially, a set of 100 sequences from GenBank were downloaded and checked for their gender: whether they were female (F) or male (M) in origin. Our analysis of the new data confirms the known drastic differences between the F/M mitogenome lines in mussels. Phylogenetic reconstructions of the F-lines were performed using the combined set of genetic markers, reconstructing only protein-coding genes (PCGs), only rRNA + tRNA genes, and all genes. Additionally, the analysis includes the usage of nucleotide sequences composed of other data matrices, such as 20-68 mitogenome sequences. The time of divergence from MRCA, estimated via BEAST2, for Mytilidae is close to 293 Mya, suggesting that they originate in the Silurian Period. From all these data, a consensus for the phylogeny of the subfamily of Mytilinae and its systematics is suggested. In particular, the long-debated argument on mussel systematics was resolved as to whether Mytilidae, and the subfamily of Mytilinae, are monophyletic. The topology signal, which was strongly resolved in this paper and in the literature, has refuted the theory regarding the monophyly of Mytilinae.