Transcriptional activation mediated by binding of a plant GATA-type zinc finger protein AGP1 to the AG-motif (AGATCCAA) of the wound-inducible Myb gene NtMyb2
Transcriptional activation mediated by binding of a plant GATA-type zinc finger protein AGP1 to the AG-motif (AGATCCAA) of the wound-inducible Myb gene NtMyb2
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DOI：
10.1046/j.1365-313x.2003.01899.x
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发表时间：
2003-11-01
期刊：
影响因子：
7.2
通讯作者：
Hirochika, H
中科院分区：
文献类型：
--
作者：
Sugimoto, K;Takeda, S;Hirochika, H
NtMyb 2是烟草反转录转座子Tto 1和防御相关基因苯丙氨酸解氨酶（PAL）的调节子，它们受各种胁迫刺激如创伤或激发子处理诱导。NtMyb 2也通过创伤或激发子处理来诱导，并且在转录水平上被调节。在这项研究中，NtMyb 2启动子的突变分析和体内功能获得性分析表明，序列AGATCCAA，命名为AG基序，是一个顺式元件足以赋予响应创伤和激发子治疗。此外，我们还利用Southwestern方法克隆了一个能与AG基序特异结合的GATA型锌指蛋白，命名为AG基序结合蛋白（AGP1）。结构域分析表明，AGP 1的结合活性不仅需要GATA型锌指结构域，而且还需要下游的His（2）基序，表明AGP具有一个新的GATA型锌指结构域。AGP1可以激活烟草原生质体中含有AG基序的启动子的表达，表明AGP1是NtMyb 2的正调控因子。我们还发现，AGP1的结合活性是高度增强的腺嘌呤甲基化的AG基序的细菌坝甲基化酶。
NtMyb2 is a regulator of the tobacco retrotransposon Tto1 and the defense-related gene phenylalanine ammonia lyase (PAL), which are induced by various stress stimuli such as wounding or elicitor treatment. NtMyb2 is also induced by wounding or elicitor treatment and is regulated at the transcriptional level. In this study, mutational analysis of the promoter of NtMyb2 and gain-of-function analysis in vivo showed that the sequence AGATCCAA, named the AG-motif, is a cis-element sufficient to confer responsiveness to wounding and elicitor treatment. Furthermore, by using the south-western method, we cloned cDNAs encoding a GATA-type zinc finger protein, which can specifically bind to the AG-motif, named AG-motif binding Protein (AGP1). Domain analysis revealed that not only the GATA-type zinc finger region but also the downstream His(2) motif of AGP1 is required for binding activity, showing that the AGP has a novel GATA-type zinc finger domain. AGP1 can activate expression from promoters containing the AG-motif in tobacco protoplasts, indicating that AGP1 is a positive regulator of NtMyb2. We also found that the AGP1 binding activity is highly enhanced by adenine methylation of the AG-motif by bacterial dam methylase.