School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
J Genet Genomics. 2010 Jan;37(1):37-46. doi: 10.1016/S1673-8527(09)60023-0.
To understand the molecular mechanism of male reproductive development in the model crop rice, we isolated a complete male sterile mutant post-meiotic deficient anther1 (pda1) from a gamma-ray-treated rice mutant library. Genetic analysis revealed that the pda1 mutant was controlled by a recessive nucleus gene. The pda1 mutant anther seemed smaller with white appearance. Histological analysis demonstrated that the pda1 mutant anther undergoes normal early tapetum development without obvious altered meiosis. However, the pda1 mutant displayed obvious defects in postmeiotic tapetal development, abnormal degeneration occurred in the tapetal cells at stage 9 of anther development. Also we observed abnormal lipidic Ubisch bodies from the tapetal layer of the pda1 mutant, causing no obvious pollen exine formation. RT-PCR analysis indicated that the expression of genes involved in anther development including GAMYB, OsC4 and Wax-deficient anther1 (WDA1) was greatly reduced in the pda1 mutant anther. Using map-based cloning approach, the PDA1 gene was finely mapped between two markers HLF610 and HLF627 on chromosome 6 using 3,883 individuals of F(2) population. The physical distance between HLF610 and HLF627 was about 194 kb. This work suggests that PDA1 is required for post-meiotic tapetal development and pollen/microspore formation in rice.
为了理解模型作物水稻雄性生殖发育的分子机制，我们从伽马射线处理的水稻突变体文库中分离出一个完全雄性不育的减数后缺陷花药 1 型（pda1）突变体。遗传分析表明，pda1 突变体受隐性核基因控制。pda1 突变体花药似乎较小，呈白色外观。组织学分析表明，pda1 突变体花药经历了正常的早期绒毡层发育，减数分裂没有明显改变。然而，pda1 突变体在后减数期绒毡层发育中表现出明显的缺陷，在花药发育的第 9 期绒毡层细胞发生异常退化。此外，我们还观察到 pda1 突变体的绒毡层中有异常的脂性 Ubisch 体，导致花粉外壁形成不明显。RT-PCR 分析表明，pda1 突变体花药中参与花药发育的基因，包括 GAMYB、OsC4 和 Wax-deficient anther1（WDA1）的表达大大降低。利用基于图谱的克隆方法，在 F2 群体的 3883 个个体中，将 PDA1 基因精细定位在染色体 6 上的两个标记 HLF610 和 HLF627 之间。HLF610 和 HLF627 之间的物理距离约为 194kb。这项工作表明，PDA1 是水稻减数后绒毡层发育和花粉/小孢子形成所必需的。
