背景回顾：Heat stress has a deleterious effect on male fertility in rice (Oryza sativa), but mechanisms to protect against heat stress in rice male gametophytes are poorly understood. 

主要发现：Here, we have isolated and characterized a heat-sensitive male-sterile rice mutant, heat shock protein60-3b (oshsp60-3b), that shows normal fertility at optimal temperatures but decreasing fertility as temperatures increase. 

结果1-hsp60-3b突变表型：High temperatures interfered with pollen starch granule formation and ROS scavenging in oshsp60-3b anthers, leading to cell death and pollen abortion. 

结果2-HSP60-3B热胁迫响应及过表达表型：In line with the mutant phenotypes, OsHSP60-3B was rapidly upregulated in response to heat shock and its protein products were localized to the plastid. Critically, overexpression of OsHSP60-3B enhanced the heat tolerance of pollen in transgenic plants. 

结果3-HSP60-3B互作蛋白FLO6：We demonstrated that OsHSP60-3B interacted with FLOURY ENDOSPERM6 (FLO6) in plastids, a key component involved in the starch granule formation in the rice pollen. Western-blot results showed that FLO6 level was substantially decreased in oshsp60-3b anthers at high temperature, indicating that OsHSP60-3B is required to stabilize FLO6 when temperatures exceed optimal conditions. 

结论：We suggest that in response to high temperature, OsHSP60-3B interacts with FLO6 to regulate starch granule biogenesis in rice pollen and attenuates ROS levels in anthers to ensure normal male gametophyte development in rice.

热胁迫对于水稻的雄性育性具有有害作用，但是水稻雄配子体的热胁迫抗性机制仍不清楚。本文中，作者分离并鉴定到了一个热敏感的水稻雄性育性突变体oshsp60-3b，其在适宜温度下表现出正常的育性，但是在温度升高时育性降低。高温会干扰oshsp60-3b突变体花药中花粉淀粉粒的形成以及ROS清除，导致细胞死亡和花粉败育。与突变体表型一致的是，OsHSP60-3B在响应热胁迫时快速上调，并且其蛋白产物定位于质体。过表达OsHSP60-3B基因能够增强转基因植株花粉的热耐受性。作者发现OsHSP60-3B能够在质体中与水稻花粉淀粉粒形成关键组分FLO6发生互作。Western-blot结果显示，高温下oshsp60-3b突变体花药中FLO6蛋白水平大幅降低，表明OsHSP60-3B能够在温度不适宜的条件下维持FLO6蛋白稳定性。作者提出水稻OsHSP60-3B能够响应高温与FLO6互作以调控花粉中的淀粉粒生物发生，同时降低花药中的ROS水平，从而保证雄配子体的正常发育。

** 梁婉琪 **