Molecular identification of BrHAB2a, one of the two AtHAB2-like proteins in Brassica rapa, is an important component of ABA signaling
Molecular identification of BrHAB2a, one of the two AtHAB2-like proteins in Brassica rapa, is an important component of ABA signaling
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BrHAB2a（甘蓝中两种 AtHAB2 样蛋白之一）的分子鉴定是 ABA 信号传导的重要组成部分
DOI：
10.1016/j.bbrc.2018.04.185
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发表时间：
2018-09-05
影响因子：
3.1
通讯作者：
Xie, Chang Gen
中科院分区：
文献类型：
--
作者：
Li, Guoqing;Hu, Xiaochen;Xie, Chang Gen
脱落酸(ABA)信号转导是许多陆地植物用来对抗环境胁迫的重要生理步骤。作为线性ABA信号通路的组成部分，Glade A蛋白磷酸酶2C(PP2C-AS)主要被ABA受体的PYRABACTIN RESISTANCE1/PYR1样/调节组分与ABA结合而抑制。在这里，我们发现白菜基因组编码14个可能的Glade A PP2C样蛋白(BrPP2C-AS)。其中两个BrPP2C-AS，Bra025964和Bra016595，与拟南芥中的HAB2(与ABI2同源)蛋白显示出高度的相似性。RNAseq数据显示，几乎所有的BrPP2C-AS，如BrHAB2a(Bra025964)和BrHAB2b(Bra016595)，至少在一个组织中高表达。BrHAB2a的过表达使ABA对拟南芥幼苗不敏感。此外，在ABA存在的情况下，AtPYL1或BrPYL1均能抑制BrHAB2a的磷酸酶活性。综上所述，这些结果表明BrHAB2a是一种功能类似PP2C-A的蛋白磷酸酶，也是油菜ABA信号转导的关键成分。(C)2018 Elsevier Inc.保留所有权利。
Abscisic acid (ABA) signaling is a vital physiological step that is used by many land plants to fight against environmental stress. As components of the linear ABA signaling pathway, Glade A protein phosphatases type 2C (PP2C-As) are mainly inhibited by PYRABACTIN RESISTANCE1/PYR1-LIKE/REGULATORY COMPONENTS OF ABA RECEPTORS (PYLs)-type receptors upon their binding to ABA. Here, we show that the genome of Brassica rapa encodes 14 putative Glade A PP2C-like proteins (BrPP2C-As). Two of these BrPP2C-As, Bra025964 and Bra016595, show high similarity to the HAB2 (Homology to ABI2) protein in Arabidopsis. RNAseq data reveal that nearly all BrPP2C-As, like BrHAB2a (Bra025964) and BrHAB2b (Bra016595), were highly expressed in at least one tissue. Overexpression of BrHAB2a conferred ABA insensitivity to Arabidopsis thaliana seedlings. Furthermore, the phosphatase activity of BrHAB2a could be inhibited by AtPYL1 or BrPYL1 in the presence of ABA. Overall, these results suggest that BrHAB2a is a functional PP2C-A like protein phosphotase and a key component of ABA signaling in Brassica rapa. (C) 2018 Elsevier Inc. All rights reserved.