Auxin abolishes SHI-RELATED SEQUENCE5-mediated inhibition of lateral root development in Arabidopsis
Auxin abolishes SHI-RELATED SEQUENCE5-mediated inhibition of lateral root development in Arabidopsis
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生长素消除了 SHI 相关序列 5 介导的拟南芥侧根发育抑制
DOI：
10.1111/nph.16115
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发表时间：
2020
期刊：
影响因子：
9.4
通讯作者：
Lu Ying-Tang
中科院分区：
文献类型：
--
作者：
Yuan Ting-Ting;Xu Heng-Hao;Li Juan;Lu Ying-Tang
侧根是植物胚后形成的根，决定着根系的结构。虽然抑制LR形成的负调控因子，并抵消生长素存在于pericardium，这些因素还没有characteristic. In这里，我们报告说，SHI相关序列5（SRS 5）是一个内在的负调节LR形成和生长素信号消除这种抑制作用的SRS 5。然而，与野生型相比，SRS 5 ox和Pro35 S：SRS 5-GFP植物中的LR原基（LRP）和LR更少，密度更低，而在rs 5 - 2功能缺失突变体中，它们更丰富，密度更高。SRS 5通过直接下调LBD 16和LBD 29的表达抑制LR的形成。生长素抑制SRS 5的表达。在arf 7 - 1 arf 19 - 1双突变体中没有观察到生长素介导的SRS 5表达抑制，这可能是因为ARF 7和ARF 19结合到SRS 5的启动子上，并抑制其对生长素的反应。总之，我们的数据表明，SRS 5通过抑制LBD 16和LBD 29的表达来负调控LR的形成，而生长素通过ARF 7和ARF 19释放这种抑制作用。
Lateral roots (LRs), which form in the plant postembryonically, determine the architecture of the root system. While negative regulatory factors that inhibit LR formation and are counteracted by auxin exist in the pericycle, these factors have not been characterised.Here, we report that SHI‐RELATED SEQUENCE5 (SRS5) is an intrinsic negative regulator of LR formation and that auxin signalling abolishes this inhibitory effect of SRS5. Whereas LR primordia (LRPs) and LRs were fewer and less dense inSRS5oxandPro35S:SRS5‐GFPplants than in the wild‐type, they were more abundant and denser in thesrs5‐2loss‐of‐function mutant. SRS5 inhibited LR formation by directly downregulating the expression ofLATERAL ORGAN BOUNDARIES‐DOMAIN 16(LBD16) andLBD29.Auxin repressedSRS5expression. Auxin‐mediated repression ofSRS5expression was not observed in thearf7‐1 arf19‐1double mutant, likely because ARF7 and ARF19 bind to the promoter ofSRS5and inhibit its expression in response to auxin.Taken together, our data reveal that SRS5 negatively regulates LR formation by repressing the expression ofLBD16andLBD29and that auxin releases this inhibitory effect through ARF7 and ARF19.