Positive regulation of AMS by TDF1 and the formation of a TDF1-AMS complex are required for anther development in Arabidopsis thaliana
Positive regulation of AMS by TDF1 and the formation of a TDF1-AMS complex are required for anther development in Arabidopsis thaliana
复制标题
拟南芥花药发育需要 TDF1 对 AMS 的正向调节以及 TDF1-AMS 复合物的形成
DOI：
10.1111/nph.14790
复制
发表时间：
2018-01-01
期刊：
影响因子：
9.4
通讯作者：
Yang, Zhong-Nan
中科院分区：
文献类型：
--
作者：
Lou, Yue;Zhou, Hai-Sheng;Yang, Zhong-Nan
绒毡层发育和花粉产生受一组绒毡层特异转录因子组成的复杂转录网络调控。在这些TF中，绒毡层发育和功能缺陷1（TDF 1）编码R2 R3 MYB因子，而小孢子败育（AMS）编码碱性螺旋-环-螺旋（bHLH）因子。然而，关于TDF 1在花药发育中的调控作用的知识仍然有限。我们在AMS（-/-）gpTDF 1：AMS-FLAG细胞系中发现了AMS的早熟转录本和AMS蛋白的缺失，这表明TDF 1调控AMS表达的时间是AMS发挥功能的先决条件。另外，TDF 1-AMS复合物还可叠加促进AMS调控基因的表达，表明TDF 1和AMS通过前馈环调控下游基因的表达。EPXB 5是TDF 1的另一个直接靶基因，编码一种β-expansin家族蛋白，在绒毡层和花粉粒中高度表达。TDF 1-AMS复合物通过前馈环协同作用以激活EXPB 5表达。TDF 1和AMS之间的调节途径的鉴定提供了一个互锁的前馈回路，该回路精确地调节支持花药发育的转录级联。
Tapetum development and pollen production are regulated by a complex transcriptional network that consists of a group of tapetum-specific Arabidopsis transcription factors (TFs). Among these TFs, DEFECTIVE IN TAPETAL DEVELOPMENT AND FUNCTION 1 (TDF1) encodes an R2R3 MYB factor, and ABORTED MICROSPORE (AMS) encodes a basic helix-loop-helix (bHLH) factor. However, knowledge regarding the regulatory role of TDF1 in anther development remains limited.Here, we discovered that TDF1 directly regulates AMS via an AACCT cis-element. We found the precocious AMS transcript and absence of AMS protein in ams(-/-) gpTDF1:AMS-FLAG lines, suggesting the timing of the TDF1-regulated AMS expression is a prerequisite for AMS functioning.We found that TDF1 interacts with AMS. Additionally, the TDF1-AMS complex additively promotes the expression of AMS-regulated genes, suggesting that TDF1 and AMS regulate the downstream genes through a feed-forward loop.EPXB5, encoding a beta-expansin family protein, is another direct target of TDF1, and it is highly expressed in the tapetum and pollen grains. The TDF1-AMS complex acts in concert to activate EXPB5 expression through a feed-forward loop. The identification of the regulatory pathway between TDF1 and AMS provides an interlocked feed-forward loop circuit that precisely regulates the transcriptional cascades that support anther development.