The Arabidopsis ABA-activated kinase OST1 phosphorylates the bZIP transcription factor ABF3 and creates a 14-3-3 binding site involved in its turnover.
The Arabidopsis ABA-activated kinase OST1 phosphorylates the bZIP transcription factor ABF3 and creates a 14-3-3 binding site involved in its turnover.
复制标题
DOI：
10.1371/journal.pone.0013935
复制
发表时间：
2010-11-10
期刊：
影响因子：
3.7
通讯作者：
Merlot S
中科院分区：
文献类型：
--
作者：
Sirichandra C;Davanture M;Turk BE;Zivy M;Valot B;Leung J;Merlot S
拟南芥中的遗传证据表明，Snf 1相关激酶2家族（SnRK 2）的成员在介导各种胁迫适应性反应中是必不可少的。最近的报道确实表明，一个特定的成员，开放气孔（OST）1，其激酶活性由胁迫激素脱落酸（阿坝）刺激，是由PYR/PYL/RCAR和进化枝A蛋白磷酸酶2C（PP 2C）蛋白组成的核心阿坝共受体复合物负调控的直接靶标。在这里，OST 1的底物偏好在全基因组范围内进行了调查。我们在体外磷酸化的半简并肽的银行，旨在评估相对磷酸化效率的位置固定的丝氨酸或苏氨酸引起的侧翼氨基酸序列的系统性变化。我们的研究结果指定ABA反应元件结合因子3（ABF 3），它控制的ABA调节转录组的一部分，作为一个真正的OST 1基板。双分子荧光互补实验表明，ABF 3直接与OST 1在活的植物细胞核中相互作用。在体外，OST 1磷酸化多个LXRXXpS/T优选基序上的ABF 3，包括位于保守的14-3-3结合位点中间的T451。使用对优选基序的磷酸化状态敏感的抗体，我们进一步表明ABF 3在体内响应于阿坝在至少一个这样的基序上被磷酸化，并且磷酸-T451对于ABF 3的稳定是重要的。总之，我们的研究结果表明，OST 1磷酸化ABF 3在体内T451产生一个14-3-3结合基序。在更广泛的生理背景下，我们提出，阿坝的长期反应，需要持续的基因表达，部分介导的ABF的ABA激活的SnRK 2驱动的稳定。
Genetic evidence in Arabidopsis thaliana indicates that members of the Snf1-Related Kinases 2 family (SnRK2) are essential in mediating various stress-adaptive responses. Recent reports have indeed shown that one particular member, OPEN STOMATA (OST)1, whose kinase activity is stimulated by the stress hormone abscisic acid (ABA), is a direct target of negative regulation by the core ABA co-receptor complex composed of PYR/PYL/RCAR and clade A Protein Phosphatase 2C (PP2C) proteins. Here, the substrate preference of OST1 was interrogated at a genome-wide scale. We phosphorylated in vitro a bank of semi-degenerate peptides designed to assess the relative phosphorylation efficiency on a positionally fixed serine or threonine caused by systematic changes in the flanking amino acid sequence. Our results designate the ABA-responsive-element Binding Factor 3 (ABF3), which controls part of the ABA-regulated transcriptome, as a genuine OST1 substrate. Bimolecular Fluorescence Complementation experiments indicate that ABF3 interacts directly with OST1 in the nuclei of living plant cells. In vitro, OST1 phosphorylates ABF3 on multiple LXRXXpS/T preferred motifs including T451 located in the midst of a conserved 14-3-3 binding site. Using an antibody sensitive to the phosphorylated state of the preferred motif, we further show that ABF3 is phosphorylated on at least one such motif in response to ABA in vivo and that phospho-T451 is important for stabilization of ABF3. All together, our results suggest that OST1 phosphorylates ABF3 in vivo on T451 to create a 14-3-3 binding motif. In a wider physiological context, we propose that the long term responses to ABA that require sustained gene expression is, in part, mediated by the stabilization of ABFs driven by ABA-activated SnRK2s.
登录
查看更多内容
DOI：
10.1073/pnas.0912021106
发表时间：
2009-12-15
影响因子：
11.1
作者：
Geiger, Dietmar;Scherzer, Soenke;Hedrich, Rainer
通讯作者：
Hedrich, Rainer
DOI：
10.1073/pnas.0505667103
发表时间：
2006-02-07
影响因子：
11.1
作者：
Furihata, T;Maruyama, K;Yamaguchi-Shinozaki, K
通讯作者：
Yamaguchi-Shinozaki, K
影响因子：
5.1
作者：
Finkelstein, R;Gampala, SSL;Rock, CD
通讯作者：
Rock, CD
影响因子：
5.1
作者：
Garcia, Mary Emily;Lynch, Tim;Finkelstein, Ruth
通讯作者：
Finkelstein, Ruth
影响因子：
7.4
作者：
Belin, Christophe;de Franco, Pierre-Olivier;Thomine, Sebastien
通讯作者：
Thomine, Sebastien