Abstract

The influence of mtDNA cytochrome c-oxidase I gene fragment variability on body length has been studied in 12 species of cyprinids, which may have hybrids with Rutilus rutilus L. and Abramis brama L., and in reciprocal hybrids (RA and AR) and alloplasmatic backcrosses (_ARR and _RAA) of roach (R) and bream (A). It has been established that the rate of nucleotide substitutions in COX1 is negatively related not only to body size but also to fish lifespan which differentiates them into two groups: group I (species with a high rate of COX1 changes and a relatively small body size) and group II (species with low sequence variability and relatively large body size). The boundary for the distinguished groups runs between species of the same genus, Leuciscus leuciscus and L. idus: with a twofold decrease in the rate of substitutions in ide, a twofold increase in body size and lifespan occurs, which indicates a decrease in the rate of cellular respiration and free radical leak, and the exact mitonuclear match respiratory complexes. Presumably, the decrease in the rate of COX1 changes in species of group II and in bleak Alburnus alburnus is associated with an increase in the size of the genome, which provides the additional protection of genes from chemical mutagens and, regardless of body size, reduces the rate of aerobic metabolism. It has been experimentally shown that mtDNA affects body length. When bream mtDNA is included in the roach nuclear genome, _ARR backcrosses have the body length of a bream and high viability, while _RAA backcrosses with roach mtDNA and the bream nuclear genome inherit the roach body length and reduce viability. Species of group II are not able to effectively use the highly polymorphic mtDNA of species of group I, which is also manifested by a violation of the inheritance of a longer bream body length in RA hybrids and leads to reproductive isolation. Group I species, such as Rutilus rutilus, can include mtDNA of both groups in their genome, which underlies sexual selection in hybridization. Accordingly, sexual size dimorphism has a genetic origin, and the body size for a potential partner can be a signal for determining the mitonuclear compatibility of genomes in respiratory complexes.

中文翻译：

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COX1基因变化率对鲤鱼杂交体型和性选择的影响

摘要

mtDNA 细胞色素c-氧化酶 I 基因片段变异性对 12 种鲤鱼体长的影响进行了研究，这可能与Rutilus rut​​ilus L. 和 Abramis brama L. 的杂交种，互惠杂交（RA 和 AR）和异质回交（_ARR 和 _RAA) 蟑螂 (R) 和鳊鱼 (A)。已经确定，COX1 中的核苷酸取代率不仅与体型呈负相关，而且与鱼类的寿命呈负相关，这将它们分为两类： I 组（COX1 变化率高且体型相对较小的物种）和第二组（序列变异性低且体型相对较大的物种）。不同类群的边界在同一属的物种之间，雅罗鱼和L。 idus：随着 ide 取代率降低两倍，体型和寿命增加两倍，这表明细胞呼吸和自由基泄漏的速率降低，并且线粒体核与呼吸复合物精确匹配。据推测，II 类物种和 bleak Alburnus alburnus 物种中 COX1 变化率的降低与基因组大小的增加有关。它为基因提供了额外的保护，使其免受化学诱变剂的影响，并且无论体型大小，都会降低有氧代谢的速率。实验表明，线粒体DNA影响体长。当鳊鱼线粒体DNA包含在蟑螂核基因组中时，_ARR回交具有鳊鱼的体长和高活力，而_RAA与蟑螂mtDNA回交，鳊鱼核基因组继承了蟑螂体长并降低了生存能力。 II组物种不能有效地利用I组物种的高度多态性mtDNA，这也表现为违反了RA杂种中较长体长的遗传并导致生殖隔离。 I 组物种，例如Rutilus rut​​ilus，的基因组中可以包含两个组的 mtDNA，这是杂交中性选择的基础。因此，性别体型二态性具有遗传起源，潜在伴侣的体型可以作为确定呼吸复合体中基因组线粒体核相容性的信号。