YUCCA-mediated auxin biogenesis is required for cell fate transition occurring during de novo root organogenesis in Arabidopsis.
YUCCA-mediated auxin biogenesis is required for cell fate transition occurring during de novo root organogenesis in Arabidopsis.
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拟南芥根器官发生过程中发生的细胞命运转变需要丝兰介导的生长素生物发生
DOI：
10.1093/jxb/erw213
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发表时间：
2016-07
影响因子：
6.9
通讯作者：
Xu L
中科院分区：
文献类型：
--
作者：
Chen L;Tong J;Xiao L;Ruan Y;Liu J;Zeng M;Huang H;Wang JW;Xu L
丝兰家族基因响应叶片外植体中的多种信号，参与生长素的生物合成，促进再生能力细胞的命运转变。许多植物器官具有在脱离或损伤后通过新器官发生再生新植物的能力。在拟南芥叶片外植体再生根器官发生过程中，内源生长素通过激活WUSCHEL相关的同源异型盒11(WOX11)，对再生细胞成为根创始细胞的命运转变起着至关重要的作用。然而，从叶片外植体脱落到生长素介导的细胞命运转换的分子事件却知之甚少。在本研究中，我们使用了一种测定吲哚-3-乙酸(IAA)浓度的方法来提供直接证据，证明生长素是在叶片外植体分离后产生的，这一过程涉及丝兰(Yucca)介导的生长素生物发生。抑制YUC可阻止WOX11的表达和感受细胞的命运转移，从而阻断生根。进一步的分析表明，YUC1和YUC4在光照和黑暗条件下对伤害的反应都很快(在4h内)，并促进叶肉和感受细胞中生长素的生物合成，而YUC5、YUC8和YUC9在黑暗条件下主要反应。此外，YUC2和YUC6通过在叶片中提供基础生长素水平来促进生根。总体而言，我们的研究表明，YUC基因在叶片外植体再生根器官发生过程中表现出对多种信号的反应分工。
YUCCA family genes act in response to multiple signals in leaf explants and contribute to de novo auxin biogenesis for fate transition of regeneration-competent cells. Many plant organs have the ability to regenerate a new plant after detachment or wounding via de novo organogenesis. During de novo root organogenesis from Arabidopsis thaliana leaf explants, endogenic auxin is essential for the fate transition of regeneration-competent cells to become root founder cells via activation of WUSCHEL-RELATED HOMEOBOX 11 (WOX11). However, the molecular events from leaf explant detachment to auxin-mediated cell fate transition are poorly understood. In this study, we used an assay to determine the concentration of indole-3-acetic acid (IAA) to provide direct evidence that auxin is produced after leaf explant detachment, a process that involves YUCCA (YUC)-mediated auxin biogenesis. Inhibition of YUC prevents expression of WOX11 and fate transition of competent cells, resulting in the blocking of rooting. Further analysis showed that YUC1 and YUC4 act quickly (within 4 hours) in response to wounding after detachment in both light and dark conditions and promote auxin biogenesis in both mesophyll and competent cells, whereas YUC5, YUC8, and YUC9 primarily respond in dark conditions. In addition, YUC2 and YUC6 contribute to rooting by providing a basal auxin level in the leaf. Overall, our study indicates that YUC genes exhibit a division of labour during de novo root organogenesis from leaf explants in response to multiple signals.