College of Life Science, Hunan Normal University, Changsha, 410081, Hunan, China.
BMC Plant Biol. 2019 Feb 11;19(1):65. doi: 10.1186/s12870-019-1666-5.
Thermo-sensitive genetic male sterile (TGMS) lines have been widely used in two-line hybrid rice breeding. The two-line hybrids have increased rice yields substantially. However, the effect of environmental temperatures on the fertility conversion is still not fully clear. In this study, we performed a tandem mass tag (TMT)-based proteomic analysis on the anthers of the TGMS line AnnongS-1 grown under permissive (low) temperature (21 °C) and restrictive (high) temperature (> 26 °C) conditions in an attempt to explore the effect of temperature on the fertility of the male sterile line.
After the AnnongS-1 plants were induced under either permissive or restrictive conditions, morphological observations and I-KI staining confirmed that the pollen grains formed under high temperature conditions were abortive while those formed under low temperature developed normally. In comparison to the plants grown under permissive conditions, the restrictive high-temperature conditions led to the differential accumulation of 89 proteins in the anthers, of which 46 were increased in abundance and 43 were decreased in abundance. Most of the subcellular compartments of the anther cells had one or more proteins that had been differentially accumulated, with the cytoplasm and chloroplast having the greatest accumulations. More than 40% of the differentially abundant proteins (DAPs) were enzymes involved in photosynthesis, energy metabolism, biosynthesis and catabolism of cellular components, metabolic regulation, defense and stress, etc. The DAPs related to protein metabolism accounted for the largest proportion (21.35%), followed by those related to defense and stress (12.36%), metabolic regulation (10.11%) and carbohydrate metabolism (8.99%), indicating that such biological processes in anther cells were more susceptible to high temperature stress.
The restrictive temperature induction caused fertility-sterility conversion in the TGMS line AnnongS-1 mainly by adversely affecting the metabolism of protein, carbohydrate and energy, and decreasing the abundances of important proteins closely related to defense and stress, thereby impeding the growth and development of the pollen and weakening the overall defense and ability to endure stress of AnnongS-1. These data are helpful for deepening our understanding of the molecular mechanism underlying fertility conversion in TGMS lines.
温敏雄性不育（TGMS）系已广泛应用于两系杂交稻的培育。两系杂种已显著提高了水稻产量。然而，环境温度对育性转换的影响仍不完全清楚。本研究采用串联质量标签（TMT）蛋白质组学分析方法，对在许可（低温）条件（21°C）和限制（高温）条件（>26°C）下生长的 TGMS 系安农 S-1 的花药进行了分析，试图探讨温度对雄性不育系育性的影响。
安农 S-1 植株在许可或限制条件下诱导后，形态观察和 I-KI 染色证实，高温条件下形成的花粉粒败育，而低温条件下形成的花粉粒正常发育。与许可条件下生长的植株相比，高温限制条件下花药中差异积累了 89 种蛋白质，其中 46 种蛋白质丰度增加，43 种蛋白质丰度降低。花药细胞的大多数亚细胞区室都有一个或多个差异积累的蛋白质，其中细胞质和叶绿体积累最多。差异丰富的蛋白质（DAP）中超过 40%是参与光合作用、能量代谢、细胞成分的生物合成和分解代谢、代谢调控、防御和应激等的酶。与蛋白质代谢相关的 DAP 占比最大（21.35%），其次是与防御和应激相关的（12.36%）、代谢调控相关的（10.11%）和碳水化合物代谢相关的（8.99%），表明花药细胞中的这些生物过程更容易受到高温胁迫的影响。
高温限制条件诱导安农 S-1 的 TGMS 系育性转换，主要是通过对蛋白质、碳水化合物和能量代谢的不利影响，降低与防御和应激密切相关的重要蛋白质的丰度，从而阻碍花粉的生长发育，削弱安农 S-1 的整体防御和耐受能力。这些数据有助于深入了解 TGMS 系育性转换的分子机制。
