Abscisic Acid Regulates Auxin Homeostasis in Rice Root Tips to Promote Root Hair Elongation.
Abscisic Acid Regulates Auxin Homeostasis in Rice Root Tips to Promote Root Hair Elongation.
复制标题
脱落酸调节水稻根尖的生长素稳态，促进根毛伸长。
DOI：
10.3389/fpls.2017.01121
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发表时间：
2017
影响因子：
5.6
通讯作者：
Wang X
中科院分区：
文献类型：
--
作者：
Wang T;Li C;Wu Z;Jia Y;Wang H;Sun S;Mao C;Wang X
脱落酸（阿坝）在植物根毛伸长过程中起重要作用，但其调控机制尚不清楚。本研究发现外源阿坝能促进水稻根毛伸长。过量表达SAPK 10（Stress/ABA-activated protein kinase 10）的转基因水稻具有较长的根毛;过量表达OsABIL 2（OsABI-Like 2）的水稻具有减弱的阿坝信号和较短的根毛，表明阿坝对根毛伸长的影响依赖于保守的PYR/PP 2C/SnRK 2阿坝信号模块。用阿坝和生长素流出抑制剂处理DR 5-GUS和OsPIN-GUS系表明ABA诱导的根毛伸长依赖于生长素极性运输。为了研究阿坝对水稻根尖的转录响应，我们将水稻根尖分为三个区域：短根毛、长根毛和根尖区;并在有或没有阿坝处理的情况下进行RNA-seq分析。对生长素运输、生物合成和代谢相关基因的研究表明，阿坝促进了生长素的生物合成和生长素在根尖的极性运输，这可能导致生长素在长根毛区的积累。我们的研究结果揭示了阿坝是如何通过与生长素的生物合成和运输相互作用来调控根毛伸长的，从而协调植物的发育。
Abscisic acid (ABA) plays an essential role in root hair elongation in plants, but the regulatory mechanism remains to be elucidated. In this study, we found that exogenous ABA can promote rice root hair elongation. Transgenic rice overexpressing SAPK10 (Stress/ABA-activated protein kinase 10) had longer root hairs; rice plants overexpressing OsABIL2 (OsABI-Like 2) had attenuated ABA signaling and shorter root hairs, suggesting that the effect of ABA on root hair elongation depends on the conserved PYR/PP2C/SnRK2 ABA signaling module. Treatment of the DR5-GUS and OsPIN-GUS lines with ABA and an auxin efflux inhibitor showed that ABA-induced root hair elongation depends on polar auxin transport. To examine the transcriptional response to ABA, we divided rice root tips into three regions: short root hair, long root hair and root tip zones; and conducted RNA-seq analysis with or without ABA treatment. Examination of genes involved in auxin transport, biosynthesis and metabolism indicated that ABA promotes auxin biosynthesis and polar auxin transport in the root tip, which may lead to auxin accumulation in the long root hair zone. Our findings shed light on how ABA regulates root hair elongation through crosstalk with auxin biosynthesis and transport to orchestrate plant development.