Identification and characterization of a semi-dominant restorer-of-fertility 1 allele in sugar beet (Beta vulgaris)
Identification and characterization of a semi-dominant restorer-of-fertility 1 allele in sugar beet (Beta vulgaris)
复制标题
DOI：
10.1007/s00122-018-3211-6
复制
发表时间：
2019-01-01
影响因子：
5.4
通讯作者：
Kubo, Tomohiko
中科院分区：
文献类型：
--
作者：
Arakawa, Takumi;Ue, Sachiyo;Kubo, Tomohiko
关键信息甜菜Rf 1基因座有许多分子变异。我们发现，其中一个分子变异体是一个弱等位基因的一个先前确定的allele.Abstractmale不育（MS）引起的核-线粒体相互作用被称为细胞质雄性不育（CMS），其中MS诱导的线粒体被抑制的核基因，恢复的生育力。Rf和rf分别是抑制和非抑制等位基因。然而，这种二分法的观点，似乎有些不满意解释最近发现的Rf基因座的分子多样性。在本研究中，我们首先确定了甜菜系NK-305作为Rf 1的新来源。我们的杂交实验表明，NK-305 Rf 1可能是一个半显性等位基因，恢复部分育性时，杂合，但完全育性时，纯合，而Rf 1从另一个甜菜线似乎是一个显性等位基因。花药绒毡层的适当退化是花粉发育的先决条件，因此，我们比较了NK-305 Rf 1杂合子和纯合子的绒毡层退化。退化发生在两种基因型，但在较小程度上的杂合子，表明NK-305 Rf 1剂量和绒毡层退化不完全导致部分生育力之间的关联。我们的蛋白质分析揭示了NK-305 Rf 1剂量与250 kDa线粒体蛋白复合物积累减少之间的定量相关性，该复合物由MS诱导线粒体编码的CMS特异性线粒体蛋白组成。Rf 1转录本的丰度与NK-305 Rf 1剂量相关。NK-305 Rf 1的分子组织表明，该等位基因通过基因间重组进化。我们建议，甜菜Rf 1基因座有一系列的多个等位基因，不同的恢复生育能力，并反映了Rf进化的复杂性。
Key messageThe sugar beet Rf1 locus has a number of molecular variants. We found that one of the molecular variants is a weak allele of a previously identified allele.AbstractMale sterility (MS) caused by nuclear-mitochondrial interaction is called cytoplasmic male sterility (CMS) in which MS-inducing mitochondria are suppressed by a nuclear gene, restorer-of-fertility. Rf and rf are the suppressing and non-suppressing alleles, respectively. This dichotomic view, however, seems somewhat unsatisfactory to explain the recently discovered molecular diversity of Rf loci. In the present study, we first identified sugar beet line NK-305 as a new source of Rf1. Our crossing experiment revealed that NK-305 Rf1 is likely a semi-dominant allele that restores partial fertility when heterozygous but full fertility when homozygous, whereas Rf1 from another sugar beet line appeared to be a dominant allele. Proper degeneration of anther tapetum is a prerequisite for pollen development; thus, we compared tapetal degeneration in the NK-305 Rf1 heterozygote and the homozygote. Degeneration occurred in both genotypes but to a lesser extent in the heterozygote, suggesting an association between NK-305 Rf1 dose and incompleteness of tapetal degeneration leading to partial fertility. Our protein analyses revealed a quantitative correlation between NK-305 Rf1 dose and a reduction in the accumulation of a 250kDa mitochondrial protein complex consisting of a CMS-specific mitochondrial protein encoded by MS-inducing mitochondria. The abundance of Rf1 transcripts correlated with NK-305 Rf1 dose. The molecular organization of NK-305 Rf1 suggested that this allele evolved through intergenic recombination. We propose that the sugar beet Rf1 locus has a series of multiple alleles that differ in their ability to restore fertility and are reflective of the complexity of Rf evolution.