Abscisic acid accumulation modulates auxin transport in the root tip to enhance proton secretion for maintaining root growth under moderate water stress
Abscisic acid accumulation modulates auxin transport in the root tip to enhance proton secretion for maintaining root growth under moderate water stress
复制标题
脱落酸积累调节根尖中的生长素运输，增强质子分泌，从而在中等水分胁迫下维持根部生长
DOI：
10.1111/nph.12004
复制
发表时间：
2013-01-01
期刊：
影响因子：
9.4
通讯作者：
Zhang, Jianhua
中科院分区：
文献类型：
--
作者：
Xu, Weifeng;Jia, Liguo;Zhang, Jianhua
维持根系生长对植物适应土壤干燥至关重要。在此，我们验证了生长素运输通过激活根尖的质子分泌来调节ABA调节的假设，以维持适度水分胁迫下的根系生长。水稻和拟南芥在水培系统下生长，并在-0.47 MPa的中度水分胁迫下，添加聚乙二醇（PEG）。除主根伸长和根毛密度外，还监测了根尖ABA积累、生长素运输和质膜H+- atp酶活性。结果表明，适度的水分胁迫增加了根端ABA的积累和生长素的运输。此外，ABA调节还参与了根尖生长素运输的调控。运输的生长素激活质膜H+- atp酶，沿根尖释放更多的质子，以适应适度的水分胁迫。在中度水分胁迫下，根尖的质子分泌对维持或促进主根伸长和根毛发育至关重要。这些结果表明，ABA的积累调节了根尖生长素的转运，从而促进了质子的分泌，维持了中等水分胁迫下根系的生长。
Maintenance of root growth is essential for plant adaptation to soil drying. Here, we tested the hypothesis that auxin transport is involved in mediating ABA's modulation by activating proton secretion in the root tip to maintain root growth under moderate water stress. Rice and Arabidopsis plants were raised under a hydroponic system and subjected to moderate water stress (-0.47 MPa) with polyethylene glycol (PEG). ABA accumulation, auxin transport and plasma membrane H+-ATPase activity at the root tip were monitored in addition to the primary root elongation and root hair density. We found that moderate water stress increases ABA accumulation and auxin transport in the root apex. Additionally, ABA modulation is involved in the regulation of auxin transport in the root tip. The transported auxin activates the plasma membrane H+-ATPase to release more protons along the root tip in its adaption to moderate water stress. The proton secretion in the root tip is essential in maintaining or promoting primary root elongation and root hair development under moderate water stress. These results suggest that ABA accumulation modulates auxin transport in the root tip, which enhances proton secretion for maintaining root growth under moderate water stress.