Leaf senescence is controlled developmentally and environmentally and is affected by numerous genes, including transcription factors. An Arabidopsis NAC domain transcription factor, ATAF2, is known to regulate biotic stress responses. Recently, we have demonstrated that ATAF2 upregulates ORE1, a key regulator of leaf senescence. Here, to investigate the function of ATAF2 in leaf senescence further, we generated and analyzed overexpressing transgenic and T-DNA inserted mutant lines. Transient expression analysis indicated that ATAF2 upregulates several NAC domain transcription factors that regulate senescence. Indeed, ATAF2 overexpression induced the expression of senescence-related genes, thereby accelerating leaf senescence, whereas the expression of such genes in ataf2 mutants was lower than that of wild type plants. Furthermore, the ataf2 mutants exhibited significant delays in dark-induced leaf senescence. It was also found that ATAF2 induces the expression of transcription factors, which both promotes and represses leaf senescence. The present study demonstrates that ATAF2 promotes leaf senescence in response to developmental and environmental signals. This article is protected by copyright. All rights reserved.

中文翻译：

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拟南芥 NAC 结构域转录因子 ATAF2 促进年龄依赖性和黑暗诱导的叶片衰老

叶片衰老受发育和环境控制，并受许多基因（包括转录因子）的影响。已知拟南芥 NAC 域转录因子 ATAF2 可调节生物应激反应。最近，我们已经证明 ATAF2 上调 ORE1，这是叶片衰老的关键调节因子。在这里，为了进一步研究 ATAF2 在叶片衰老中的功能，我们生成并分析了过表达转基因和 T-DNA 插入的突变系。瞬时表达分析表明，ATAF2 上调了几种调节衰老的 NAC 域转录因子。事实上，ATAF2 过表达诱导了衰老相关基因的表达，从而加速了叶片衰老，而这些基因在 ataf2 突变体中的表达低于野生型植物。此外，ataf2 突变体在黑暗诱导的叶片衰老中表现出显着延迟。还发现 ATAF2 诱导转录因子的表达，促进和抑制叶片衰老。本研究表明，ATAF2 响应发育和环境信号促进叶片衰老。本文受版权保护。版权所有。