| Structural highlights
3qn1 is a 2 chain structure with sequence from Arabidopsis thaliana. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: | , |
| Related: | 3k90, 3k3k, 3nmt, 3njo |
| Gene: | ABIP6, At4g17870, PYR1, RCAR11, T6K21.50 (Arabidopsis thaliana), At1g72770, F28P22.4, HAB1, P2C-HA (Arabidopsis thaliana) |
| Activity: | Phosphoprotein phosphatase, with EC number 3.1.3.16 |
| Resources: | FirstGlance, OCA, RCSB, PDBsum |
Function
[PYR1_ARATH] Receptor for abscisic acid (ABA) required for ABA-mediated responses such as stomatal closure and germination inhibition. Inhibits the activity of group-A protein phosphatases type 2C (PP2Cs) when activated by ABA.[1] [2] [3] [P2C16_ARATH] Key component and repressor of the abscisic acid (ABA) signaling pathway that regulates numerous ABA responses, such as stomatal closure, seed germination and inhibition of vegetative growth. Confers enhanced sensitivity to drought.[4] [5] [6] [7]
Publication Abstract from PubMed
The plant hormone abscisic acid (ABA) plays a crucial role in the control of the stress response and the regulation of plant growth and development. ABA binding to PYR/PYL/RCAR intracellular receptors leads to inhibition of key negative regulators of ABA signaling, i.e. clade A protein phosphatases type 2C (PP2Cs) such as ABI1 and HAB1, causing the activation of the ABA signaling pathway. In order to gain further understanding on the mechanism of hormone perception, PP2C inhibition and its implications for ABA signaling, we have performed a structural and functional analysis of the PYR1-ABA-HAB1 complex. Based on structural data, we generated a gain-of-function mutation in a critical residue of the phosphatase, hab1W385A, which abolished ABA-dependent receptor-mediated PP2C inhibition without impairing basal PP2C activity. As a result, hab1W385A caused constitutive inactivation of the protein kinase OST1 even in the presence of ABA and PYR/PYL proteins, in contrast to the receptor-sensitive HAB1, and therefore hab1W385A qualifies as a hypermorphic mutation. Expression of hab1W385A in Arabidopsis thaliana plants leads to a strong, dominant ABA-insensitivity, which demonstrates that this conserved Trp residue can be targeted for the generation of dominant clade A PP2C alleles. Moreover, our data highlight the critical role of molecular interactions mediated by Trp385 equivalent residues for clade A PP2C function in vivo and the mechanism of ABA perception and signaling.
Modulation of ABA signaling in vivo by an engineered receptor-insensitive PP2C allele.,Dupeux F, Antoni R, Betz K, Santiago J, Gonzalez-Guzman M, Rodriguez L, Rubio S, Park SY, Cutler S, Rodriguez PL, Marquez J Plant Physiol. 2011 Mar 14. PMID:21357183[8]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Santiago J, Rodrigues A, Saez A, Rubio S, Antoni R, Dupeux F, Park SY, Marquez JA, Cutler SR, Rodriguez PL. Modulation of drought resistance by the abscisic acid receptor PYL5 through inhibition of clade A PP2Cs. Plant J. 2009 Nov;60(4):575-88. doi: 10.1111/j.1365-313X.2009.03981.x. Epub 2009 , Jul 16. PMID:19624469 doi:10.1111/j.1365-313X.2009.03981.x
- ↑ Park SY, Fung P, Nishimura N, Jensen DR, Fujii H, Zhao Y, Lumba S, Santiago J, Rodrigues A, Chow TF, Alfred SE, Bonetta D, Finkelstein R, Provart NJ, Desveaux D, Rodriguez PL, McCourt P, Zhu JK, Schroeder JI, Volkman BF, Cutler SR. Abscisic acid inhibits type 2C protein phosphatases via the PYR/PYL family of START proteins. Science. 2009 May 22;324(5930):1068-71. doi: 10.1126/science.1173041. Epub 2009, Apr 30. PMID:19407142 doi:10.1126/science.1173041
- ↑ Szostkiewicz I, Richter K, Kepka M, Demmel S, Ma Y, Korte A, Assaad FF, Christmann A, Grill E. Closely related receptor complexes differ in their ABA selectivity and sensitivity. Plant J. 2010 Jan;61(1):25-35. doi: 10.1111/j.1365-313X.2009.04025.x. Epub 2009, Sep 21. PMID:19769575 doi:10.1111/j.1365-313X.2009.04025.x
- ↑ Saez A, Apostolova N, Gonzalez-Guzman M, Gonzalez-Garcia MP, Nicolas C, Lorenzo O, Rodriguez PL. Gain-of-function and loss-of-function phenotypes of the protein phosphatase 2C HAB1 reveal its role as a negative regulator of abscisic acid signalling. Plant J. 2004 Feb;37(3):354-69. PMID:14731256
- ↑ Robert N, Merlot S, N'guyen V, Boisson-Dernier A, Schroeder JI. A hypermorphic mutation in the protein phosphatase 2C HAB1 strongly affects ABA signaling in Arabidopsis. FEBS Lett. 2006 Aug 21;580(19):4691-6. Epub 2006 Jul 24. PMID:16876791 doi:10.1016/j.febslet.2006.07.047
- ↑ Saez A, Robert N, Maktabi MH, Schroeder JI, Serrano R, Rodriguez PL. Enhancement of abscisic acid sensitivity and reduction of water consumption in Arabidopsis by combined inactivation of the protein phosphatases type 2C ABI1 and HAB1. Plant Physiol. 2006 Aug;141(4):1389-99. Epub 2006 Jun 23. PMID:16798945 doi:10.1104/pp.106.081018
- ↑ Saez A, Rodrigues A, Santiago J, Rubio S, Rodriguez PL. HAB1-SWI3B interaction reveals a link between abscisic acid signaling and putative SWI/SNF chromatin-remodeling complexes in Arabidopsis. Plant Cell. 2008 Nov;20(11):2972-88. doi: 10.1105/tpc.107.056705. Epub 2008 Nov, 25. PMID:19033529 doi:10.1105/tpc.107.056705
- ↑ Dupeux F, Antoni R, Betz K, Santiago J, Gonzalez-Guzman M, Rodriguez L, Rubio S, Park SY, Cutler S, Rodriguez PL, Marquez J. Modulation of ABA signaling in vivo by an engineered receptor-insensitive PP2C allele. Plant Physiol. 2011 Mar 14. PMID:21357183 doi:10.1104/pp.110.170894
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