Publication Date:
2009-11-10
Description:
Abscisic acid (ABA) is a ubiquitous hormone that regulates plant growth, development and responses to environmental stresses. Its action is mediated by the PYR/PYL/RCAR family of START proteins, but it remains unclear how these receptors bind ABA and, in turn, how hormone binding leads to inhibition of the downstream type 2C protein phosphatase (PP2C) effectors. Here we report crystal structures of apo and ABA-bound receptors as well as a ternary PYL2-ABA-PP2C complex. The apo receptors contain an open ligand-binding pocket flanked by a gate that closes in response to ABA by way of conformational changes in two highly conserved beta-loops that serve as a gate and latch. Moreover, ABA-induced closure of the gate creates a surface that enables the receptor to dock into and competitively inhibit the PP2C active site. A conserved tryptophan in the PP2C inserts directly between the gate and latch, which functions to further lock the receptor in a closed conformation. Together, our results identify a conserved gate-latch-lock mechanism underlying ABA signalling.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2810868/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2810868/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Melcher, Karsten -- Ng, Ley-Moy -- Zhou, X Edward -- Soon, Fen-Fen -- Xu, Yong -- Suino-Powell, Kelly M -- Park, Sang-Youl -- Weiner, Joshua J -- Fujii, Hiroaki -- Chinnusamy, Viswanathan -- Kovach, Amanda -- Li, Jun -- Wang, Yonghong -- Li, Jiayang -- Peterson, Francis C -- Jensen, Davin R -- Yong, Eu-Leong -- Volkman, Brian F -- Cutler, Sean R -- Zhu, Jian-Kang -- Xu, H Eric -- R01 DK066202/DK/NIDDK NIH HHS/ -- R01 DK066202-04/DK/NIDDK NIH HHS/ -- R01 DK071662/DK/NIDDK NIH HHS/ -- R01 DK071662-05/DK/NIDDK NIH HHS/ -- R01 GM087413/GM/NIGMS NIH HHS/ -- R01 GM087413-01/GM/NIGMS NIH HHS/ -- R01 HL089301/HL/NHLBI NIH HHS/ -- R01 HL089301-03/HL/NHLBI NIH HHS/ -- England -- Nature. 2009 Dec 3;462(7273):602-8. doi: 10.1038/nature08613.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Avenue, N.E., Grand Rapids, Michigan 49503, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19898420" target="_blank"〉PubMed〈/a〉
Keywords:
Abscisic Acid/*metabolism
;
Arabidopsis/genetics/metabolism/*physiology
;
Arabidopsis Proteins/*chemistry/genetics/metabolism/*physiology
;
Binding Sites
;
DNA Mutational Analysis
;
*Models, Molecular
;
Plants, Genetically Modified
;
Protein Binding
;
Protein Structure, Tertiary
;
Signal Transduction/*physiology
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
