Abscisic acid prevents pollen abortion under high-temperature stress by mediating sugar metabolism in rice spikelets
Abscisic acid prevents pollen abortion under high-temperature stress by mediating sugar metabolism in rice spikelets
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脱落酸通过介导水稻小穗中的糖代谢来防止高温胁迫下花粉败育
DOI：
10.1111/ppl.12759
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发表时间：
2019-03-01
影响因子：
6.4
通讯作者：
Fu Guanfu
中科院分区：
文献类型：
--
作者：
Rezaul, Islam Md;Feng Baohua;Fu Guanfu
花粉母细胞减数分裂阶段的热胁迫导致水稻花粉不育，其活性氧（ROS）和糖稳态受到不利影响。这种损伤可被脱落酸（ABA）逆转，但热胁迫下水稻颖花中ABA、糖代谢、ROS和热休克蛋白之间相互作用的机制尚不清楚。在PMC减数分裂期叶前喷施ABA及其生物合成抑制剂氟酮后，浙富802和fgl两个基因型水稻经受了40℃的高温胁迫。结果表明，外源施用ABA可降低因热胁迫引起的花粉不育性。这是通过多种方式实现的，包括：增加可溶性糖、淀粉和非结构性碳水化合物的水平，显著提高热休克蛋白（HSP24.1和HSP71.1）和糖代谢和转运相关基因（如蔗糖转运蛋白（SUT）基因、蔗糖合成酶（SUS）基因和转化酶（INV）基因）的相对表达水平，以及增加抗氧化活性，增加颖花中三磷酸腺苷和内源ABA的含量。简而言之，在热胁迫前外源施用ABA可增强蔗糖转运，加速蔗糖代谢，维持碳平衡和能量稳态，从而促进水稻耐热性。
Heat stress at the pollen mother cell (PMC) meiotic stage leads to pollen sterility in rice, in which the reactive oxygen species (ROS) and sugar homeostasis are always adversely affected. This damage is reversed by abscisic acid (ABA), but the mechanisms underlying the interactions among the ABA, sugar metabolism, ROS and heat shock proteins in rice spikelets under heat stress are unclear. Two rice genotypes, Zhefu802 (a recurrent parent) and fgl (its near-isogenic line) were subjected to heat stress of 40 degrees C after pre-foliage sprayed with ABA and its biosynthetic inhibitor fluridone at the meiotic stage of PMC. The results revealed that exogenous application of ABA reduced pollen sterility caused by heat stress. This was achieved through various means, including: increased levels of soluble sugars, starch and non-structural carbohydrates, markedly higher relative expression levels of heat shock proteins (HSP24.1 and HSP71.1) and genes related to sugar metabolism and transport, such as sucrose transporters (SUT) genes, sucrose synthase (SUS) genes and invertase (INV) genes as well as increased antioxidant activities and increased content of adenosine triphosphate and endogenous ABA in spikelets. In short, exogenous application of ABA prior to heat stress enhanced sucrose transport and accelerated sucrose metabolism to maintain the carbon balance and energy homeostasis, thus ABA contributed to heat tolerance in rice.