Obata Mayu, Sano Natsumi, Kawamura Kouichi, Komaru Akira
Faculty of Bioresources, Mie University, 1577 Kurimamachiya, Tsu 514-8507, Japan.
Dev Growth Differ. 2007 May;49(4):335-44. doi: 10.1111/j.1440-169X.2007.00930.x.
In Mytilus mussels, paternal mitochondrial DNA (mtDNA) from sperm is known to be transmitted to offspring. This phenomenon is called doubly uniparental inheritance (DUI). Under DUI, sperm mtDNA (M type) is inherited only by males. Female mussels receive maternal mtDNA (F type). However, in our previous study, we showed female and unfertilized eggs have both F and M types. We hypothesized that the two M types both from sperm and unfertilized eggs were transmitted to offspring. To test the hypothesis, we examined the number of M type haplotypes in mature M. galloprovincialis. The M type in larvae was compared with those of the parents. Cross experiments were carried out to test the inheritance of M type. In six of 20 mature mussels, two M types were detected by sequence analysis and polymerase chain reaction-restriction fragment length polymorphism. In cross experiments of larval samples from five of 12 crosses, double peak wave was observed by single nucleotide polymorphisms analysis. In these larval samples, the higher peak wave was identical to the parental M type. Larvae received much more paternal M type than the maternal ones. We demonstrated that two M types from sperm and unfertilized eggs were transmitted to offspring in M. galloprovincialis.
在贻贝中，已知精子中的父系线粒体DNA（mtDNA）会传递给后代。这种现象被称为双单亲遗传（DUI）。在DUI模式下，精子mtDNA（M型）仅由雄性遗传。雌性贻贝接受母系mtDNA（F型）。然而，在我们之前的研究中，我们发现雌性和未受精卵中同时存在F型和M型。我们推测来自精子和未受精卵的两种M型都会传递给后代。为了验证这一假设，我们检查了成熟的地中海贻贝中M型单倍型的数量。将幼虫中的M型与亲本的M型进行比较。进行杂交实验以测试M型的遗传情况。在20个成熟贻贝中的6个中，通过序列分析和聚合酶链反应-限制性片段长度多态性检测到两种M型。在12个杂交组合中5个杂交组合的幼虫样本的杂交实验中，通过单核苷酸多态性分析观察到双峰波。在这些幼虫样本中，较高的峰波与亲本M型相同。幼虫从父本获得的M型比母本的多得多。我们证明了来自精子和未受精卵的两种M型会传递给地中海贻贝的后代。
