Publication Date:
2009-11-26
Description:
The phytohormone abscisic acid (ABA) acts in seed dormancy, plant development, drought tolerance, and adaptive responses to environmental stresses. Structural mechanisms mediating ABA receptor recognition and signaling remain unknown but are essential for understanding and manipulating abiotic stress resistance. Here, we report structures of pyrabactin resistance 1 (PYR1), a prototypical PYR/PYR1-like (PYL)/regulatory component of ABA receptor (RCAR) protein that functions in early ABA signaling. The crystallographic structure reveals an alpha/beta helix-grip fold and homodimeric assembly, verified in vivo by coimmunoprecipitation. ABA binding within a large internal cavity switches structural motifs distinguishing ABA-free "open-lid" from ABA-bound "closed-lid" conformations. Small-angle x-ray scattering suggests that ABA signals by converting PYR1 to a more compact, symmetric closed-lid dimer. Site-directed PYR1 mutants designed to disrupt hormone binding lose ABA-triggered interactions with type 2C protein phosphatase partners in planta.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2835493/" 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/PMC2835493/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Nishimura, Noriyuki -- Hitomi, Kenichi -- Arvai, Andrew S -- Rambo, Robert P -- Hitomi, Chiharu -- Cutler, Sean R -- Schroeder, Julian I -- Getzoff, Elizabeth D -- ES010337/ES/NIEHS NIH HHS/ -- GM060396/GM/NIGMS NIH HHS/ -- GM37684/GM/NIGMS NIH HHS/ -- P42 ES010337/ES/NIEHS NIH HHS/ -- P42 ES010337-10S20008/ES/NIEHS NIH HHS/ -- R01 GM060396/GM/NIGMS NIH HHS/ -- R01 GM060396-08/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 2009 Dec 4;326(5958):1373-9. doi: 10.1126/science.1181829. Epub 2009 Oct 22.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Division of Biological Sciences, Cell and Developmental Biology Section, University of California at San Diego, La Jolla, CA 92093, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19933100" target="_blank"〉PubMed〈/a〉
Keywords:
Abscisic Acid/*metabolism
;
Amino Acid Motifs
;
Amino Acid Sequence
;
Arabidopsis Proteins/*chemistry/genetics/*metabolism
;
Binding Sites
;
Crystallography, X-Ray
;
Immunoprecipitation
;
Membrane Transport Proteins/*chemistry/genetics/*metabolism
;
Models, Molecular
;
Molecular Sequence Data
;
Mutagenesis, Site-Directed
;
Mutant Proteins/chemistry/metabolism
;
Phosphoprotein Phosphatases/metabolism
;
Protein Binding
;
Protein Conformation
;
Protein Multimerization
;
Protein Structure, Secondary
;
Protein Subunits/chemistry/metabolism
;
Scattering, Small Angle
;
*Signal Transduction
;
X-Ray Diffraction
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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