Differential regulation of TGA transcription factors by post-transcriptional control
Differential regulation of TGA transcription factors by post-transcriptional control
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DOI：
10.1046/j.1365-313x.2002.01461.x
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发表时间：
2002-12-01
期刊：
影响因子：
7.2
通讯作者：
Lam, E
中科院分区：
文献类型：
--
作者：
Pontier, D;Privat, I;Lam, E
转录因子通常属于多基因家族，它们在特定调控网络中的个体贡献仍然难以评估。在这里，我们表明，特定的成员从一个家庭的保守的拟南芥bZIP转录因子，TGA蛋白质，调节其蛋白质的稳定性，由发育阶段特异性蛋白水解。使用代表TGA因子家族不同亚类成员的三种不同拟南芥TGA因子的GFP融合物，我们证明其中两种TGA蛋白是成熟叶细胞中蛋白质水解的特异性靶向蛋白质。使用supershift凝胶迁移率测定，我们发现了类似的调节的同源蛋白质相比，花椰菜花叶病毒（CaMV）35S启动子下表达的GFP融合蛋白的证据。使用各种抑制剂，我们表明，这三个TGA因子中的至少一个的表达可以通过抑制蛋白酶体介导的蛋白水解来稳定。这项研究表明，TGA转录因子可能受到不同的靶向蛋白水解途径的调节，这些途径可以调节多基因家族中特定成员在复杂调控途径中的贡献。
Transcription factors often belong to multigene families and their individual contribution in a particular regulatory network remains difficult to assess. We show here that specific members from a family of conserved Arabidopsis bZIP transcription factors, the TGA proteins, are regulated in their protein stability by developmental stage-specific proteolysis. Using GFP fusions of three different Arabidopsis TGA factors that represent members of distinct subclasses of the TGA factor family, we demonstrate that two of these TGA proteins are specifically targeted for proteolysis in mature leaf cells. Using a supershift gel mobility assay, we found evidence for similar regulation of the cognate proteins as compared to the GFP fusion proteins expressed under the cauliflower mosaic virus ( CaMV) 35S promoter. Using various inhibitors, we showed that the expression of at least one of these three TGA factors could be stabilized by inhibition of proteasome-mediated proteolysis. This study indicates that TGA transcription factors may be regulated by distinct pathways of targeted proteolysis that can serve to modulate the contribution of specific members of a multigene family in complex regulatory pathways.