Key Laboratory of Crop Physiology Ecology and Genetic Breeding Ministry of Education, Jiangxi Agricultural University, Nanchang, 330045, China.
College of Bioscience and Bioengineering, Jiangxi Agricultural University, Nanchang, 330045, China.
Biochem Genet. 2022 Dec;60(6):2268-2285. doi: 10.1007/s10528-022-10217-4. Epub 2022 Mar 24.
To further understand the molecular mechanism for rice male reproduction, a rice male sterile mutant paa1 was screened from the rice mutant library generated by treatment with Coγ-rays. Genetic analysis revealed that paa1 is controlled by a single- recessive nuclear gene, and the anthers of the paa1 mutant were smaller than those of WT plants with a white color. Histological analysis demonstrated that the anthers of the paa1 mutant began to turn abnormal at the microspore stage after meiosis, with abnormal degradation of tapetum, deformed Ubisch bodies, and defective pollen exine. TUNEL assay results also confirmed the delay of tapetum PCD in paa1. Map-based cloning was performed for the PAA1 location. As a result, PAA1 was located in a 88-kb region at the end of chromosome 10, which comprises a total of seven candidate genes, and no genes related to anther development have been reported in this region. The results indicate that PAA1 is an essential gene in regulating tapetum development and pollen/microspore formation after rice meiosis.
为了进一步了解水稻雄性生殖的分子机制，我们从 Coγ射线处理生成的水稻突变体库中筛选出一个水稻雄性不育突变体 paa1。遗传分析表明，paa1 由一个单隐性核基因控制，其花药小于 WT 植株的花药，呈白色。组织学分析表明，paa1 突变体的花药在减数分裂后小孢子阶段开始出现异常，绒毡层异常降解，Ubiisch 体变形，花粉外壁缺陷。TUNEL 检测结果也证实了 paa1 中绒毡层 PCG 的延迟。我们对 PAA1 位置进行了基于图谱的克隆。结果表明，PAA1 位于第 10 号染色体末端的 88kb 区域内，共包含七个候选基因，而在该区域尚未报道与花药发育相关的基因。这些结果表明 PAA1 是一个调控水稻减数分裂后绒毡层发育和花粉/小孢子形成的必需基因。
