Ministry of Education Key Laboratory of Crop Heterosis and Utilization, National Center for Evaluation of Agricultural Wild Plants (Rice), Beijing Key Laboratory of Crop Genetic Improvement, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China.
Ministry of Education Key Laboratory of Crop Heterosis and Utilization, National Center for Evaluation of Agricultural Wild Plants (Rice), Beijing Key Laboratory of Crop Genetic Improvement, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
Plant Physiol. 2019 May;180(1):356-366. doi: 10.1104/pp.18.01374. Epub 2019 Feb 15.
The emergence of sterile individuals in the hybrid backcross progeny of wild and cultivated rice limits the use of wild rice alleles for improving cultivated rice, but the molecular mechanisms underlying this sterility remain unclear. Here, we identified the semisterile introgression line YIL42, derived from a cross between the rice variety Teqing () and accession YJCWR (Yuanjiang common wild rice), which exhibits semisterility. Using positional cloning, we isolated (), which encodes a nuclear-membrane localized protein containing an armadillo repeat domain. A mutation in at position 1819 (1819) converts a stop codon into an Arg (R) codon, causing delayed termination of protein translation. Analysis of transgenic lines indicated that the difference in ESA1 protein structure between -derived and Teqing-derived affects female gamete abortion during early mitosis. Fertility investigation and expression analysis indicated that the interaction between and unknown gene(s) of Teqing affects spikelet fertility of the hybrid backcross progeny. The allele is present in but absent in , suggesting that variation in may be associated with interspecific hybrid incompatibility between wild and cultivated rice. Our findings provide insight into the molecular mechanism underlying female sterility, which is useful for improving the panicle seed setting rate of rice and for developing a strategy to overcome interspecific hybrid sterility between cultivated rice and wild rice.
在野生稻和栽培稻的杂交回交后代中出现无菌个体，限制了利用野生稻等位基因来改良栽培稻，但这种不育性的分子机制尚不清楚。在这里，我们鉴定了半不育的导入系 YIL42，它是由水稻品种特青（）和元江普通野生稻（Yuanjiang common wild rice） accession YJCWR 杂交产生的，表现为半不育。通过定位克隆，我们分离了 （），它编码一种定位于核膜的蛋白，含有一个重复结构域。在 1819 位（1819）的突变将一个终止密码子转换为精氨酸（R）密码子，导致蛋白翻译的延迟终止。对转基因系的分析表明，来源于 和特青的 蛋白结构的差异影响早期有丝分裂过程中雌性配子的败育。育性调查和表达分析表明， 和特青未知基因（s）之间的相互作用影响杂种回交后代小穗的育性。 等位基因存在于 中，但不存在于 中，这表明 中的变异可能与野生稻和栽培稻之间的种间杂种不育有关。我们的研究结果为雌性不育的分子机制提供了深入的了解，这对于提高水稻的穗结实率和开发克服栽培稻和野生稻种间杂种不育的策略是有用的。
