5ecq: Difference between revisions

No edit summary
No edit summary
Line 13: Line 13:
<div style="background-color:#fffaf0;">
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
== Publication Abstract from PubMed ==
Acyl acid amido synthetases of the GH3 family act as critical prereceptor modulators of plant hormone action; however, the molecular basis for their hormone selectivity is unclear. Here, we report the crystal structures of benzoate-specific Arabidopsis thaliana AtGH3.12/PBS3 and jasmonic acid (JA)-specific AtGH3.11/JAR1. These structures, combined with biochemical analysis, define features for the conjugation of amino acids to diverse acyl acid substrates and highlight the importance of conformational changes in the C-terminal domain for catalysis. We also identify residues forming the acyl acid binding site across the GH3 family and residues critical for amino acid recognition. Our results demonstrate how a highly adaptable three-dimensional scaffold is used for the evolution of promiscuous activity across an enzyme family for modulation of plant signaling molecules.
Far-red (FR) light-coupled jasmonate (JA) signaling is necessary for plant defense and development. FR insensitive 219 (FIN219) is a member of the Gretchen Hagen 3 (GH3) family of proteins in Arabidopsis and belongs to the adenylate-forming family of enzymes. It directly controls biosynthesis of jasmonoyl-isoleucine in JA-mediated defense responses and interacts with FIN219-interacting protein 1 (FIP1) under FR light conditions. FIN219 and FIP1 are involved in FR light signaling and are regulators of the interplay between light and JA signaling. However, how their interactions affect plant physiological functions remains unclear. Here, we demonstrate the crystal structures of FIN219-FIP1 while binding with substrates at atomic resolution. Our results show an unexpected FIN219 conformation and demonstrate various differences between this protein and other members of the GH3 family. We show that the rotated C-terminal domain of FIN219 alters ATP binding and the core structure of the active site. We further demonstrate that this unique FIN219-FIP1 structure is crucial for increasing FIN219 activity and determines the priority of substrate binding. We suggest that the increased FIN219 activity resulting from the complex form, a conformation for domain switching, allows FIN219 to switch to its high-affinity mode and thereby enhances JA signaling under continuous FR light conditions.


Structural Basis for Prereceptor Modulation of Plant Hormones by GH3 Proteins.,Westfall CS, Zubieta C, Herrmann J, Kapp U, Nanao MH, Jez JM Science. 2012 May 24. PMID:22628555<ref>PMID:22628555</ref>
Structural basis of jasmonate-amido synthetase FIN219 in complex with glutathione S-transferase FIP1 during the JA signal regulation.,Chen CY, Ho SS, Kuo TY, Hsieh HL, Cheng YS Proc Natl Acad Sci U S A. 2017 Feb 21. pii: 201609980. doi:, 10.1073/pnas.1609980114. PMID:28223489<ref>PMID:28223489</ref>


From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA