Plant Breeding, Genetics and Biochemistry Division, International Rice Research Institute, Metro Manila, Philippines.
Mol Plant. 2011 Jan;4(1):59-69. doi: 10.1093/mp/ssq039. Epub 2010 Jul 19.
Crop yield is most sensitive to water deficit during the reproductive stage. For rice, the most sensitive yield component is spikelet fertility and the most sensitive stage is immediately before heading. Here, we examined the effect of drought on the anther proteome of two rice genotypes: Moroberekan and IR64. Water was withheld for 3 d before heading (3DBH) in well watered controls for 5 d until the flag leaf relative water content (RWC) had declined to 45-50%. Plants were then re-watered and heading occurred 2-3 d later, representing a delay of 4-5 d relative to controls. The anther proteins were separated at 3 DBH, at the end of the stress period, and at heading in stressed/re-watered plants and controls by two-dimensional (2-D) gel electrophoresis, and 93 protein spots were affected reproducibly in abundance by drought during the experiment across two rice genotypes. After drought stress, upon re-watering, expressions of 24 protein spots were irreversible in both genotypes, 60 protein spots were irreversible in IR64 but reversible in Moroberekan, only nine protein spots were irreversible in Moroberekan while reversible in IR64. Among them, there were 14 newly drought-induced protein spots in IR64; none of them was reversible on re-watering. However, there were 13 newly drought-induced protein spots in Moroberekan, 10 of them were reversible on re-watering, including six drought-induced protein spots that were not reversed in IR64. Taken together, our proteomics data reveal that drought-tolerant genotype Moroberekan possessed better recovery capability following drought and re-watering at the anther proteome level than the drought-sensitive genotype IR64. The disruptions of drought to rice anther development and pollen cell functions are also discussed in the paper.
作物产量在生殖阶段对水分亏缺最为敏感。对于水稻而言，最敏感的产量构成因素是小穗育性，最敏感的阶段是抽穗前。在这里，我们研究了干旱对两个水稻基因型（Moroberekan 和 IR64）的花药蛋白质组的影响。在充分浇水的对照中，在抽穗前 3 天（3DBH）停水 5 天，直到旗叶相对含水量（RWC）下降到 45-50%。然后，植物重新浇水，2-3 天后出现抽穗，相对于对照延迟了 4-5 天。在 3DBH、胁迫期结束时和胁迫/浇水后的植物和对照中，通过二维（2-D）凝胶电泳分离花药蛋白质，在两个水稻基因型的实验中，93 个蛋白质斑点的丰度受到干旱的影响是可重复的。在干旱胁迫后，重新浇水时，两个基因型中 24 个蛋白质斑点的表达是不可逆转的，IR64 中有 60 个蛋白质斑点的表达是不可逆转的，而 Moroberekan 中有 60 个蛋白质斑点的表达是不可逆转的，Moroberekan 中只有 9 个蛋白质斑点的表达是不可逆转的，而 IR64 中只有 9 个蛋白质斑点的表达是不可逆转的。其中，IR64 中有 14 个新的干旱诱导蛋白质斑点；在重新浇水时，没有一个是可逆的。然而，在 Moroberekan 中有 13 个新的干旱诱导蛋白质斑点，其中 10 个是可逆的，包括在 IR64 中没有逆转的 6 个干旱诱导蛋白质斑点。总之，我们的蛋白质组学数据表明，耐旱基因型 Moroberekan 在花药蛋白质组水平上，在干旱和重新浇水后具有比敏感基因型 IR64 更好的恢复能力。本文还讨论了干旱对水稻花药发育和花粉细胞功能的破坏。
