Institute of Cytology and Genetics of the Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia.
Institute of Cytology and Genetics of the Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia; Novosibirsk State University, Novosibirsk, Russia.
Mol Phylogenet Evol. 2021 Jul;160:107136. doi: 10.1016/j.ympev.2021.107136. Epub 2021 Mar 6.
Plastids and mitochondria have their own small genomes, which do not undergo meiotic recombination and may have evolutionary fates different from each other and that of the nuclear genome. For the first time, we sequenced mitochondrial genomes of pea (Pisum L.) from 42 accessions mostly representing diverse wild germplasm from throughout the wild pea geographical range. Six structural types of the pea mitochondrial genome were revealed. From the same accessions, plastid genomes were sequenced. Phylogenetic trees based on the plastid and mitochondrial genomes were compared. The topologies of these trees were highly discordant, implying not less than six events of hybridisation between diverged wild peas in the past, with plastids and mitochondria differently inherited by the descendants. Such discordant inheritance of organelles could have been driven by plastid-nuclear incompatibility, which is known to be widespread in crosses involving wild peas and affects organellar inheritance. The topology of the phylogenetic tree based on nucleotide sequences of a nuclear gene, His5, encoding a histone H1 subtype, corresponded to the current taxonomy and resembled that based on the plastid genome. Wild peas (Pisum sativum subsp. elatius s.l.) inhabiting Southern Europe were shown to be of hybrid origin, resulting from crosses of peas related to those presently inhabiting the eastern Mediterranean in a broad sense. These results highlight the roles of hybridisation and cytonuclear conflict in shaping plant microevolution.
质体和线粒体都有自己的小基因组，这些基因组不经历减数分裂重组，可能与核基因组以及彼此的进化命运不同。我们首次对来自 42 个豌豆（Pisum L.）品系的线粒体基因组进行了测序，这些品系主要代表了来自整个野生豌豆地理范围的多样化野生种质资源。揭示了豌豆线粒体基因组的六种结构类型。从相同的品系中，我们还对质体基因组进行了测序。比较了基于质体和线粒体基因组的系统发育树。这些树的拓扑结构高度不一致，这意味着在过去，分化的野生豌豆之间至少发生了六次杂交事件，质体和线粒体通过后代的不同方式遗传。细胞器的这种不匹配的遗传可能是由质体-核不相容性驱动的，这种不相容性在涉及野生豌豆的杂交中广泛存在，并影响细胞器的遗传。基于编码组蛋白 H1 亚型的核基因 His5 的核苷酸序列构建的系统发育树的拓扑结构与当前的分类学一致，与基于质体基因组构建的系统发育树相似。来自南欧的野生豌豆（Pisum sativum subsp. elatius s.l.）被证明是杂交起源的，是由与现今广泛分布于地中海东部的豌豆相关的豌豆杂交形成的。这些结果强调了杂交和细胞质-核冲突在塑造植物微观进化中的作用。
