title: Design and Functional Characterization of a Novel Abscisic Acid Analog.
abstract: The phytohormone abscisic acid (ABA) plays a crucial role in mediating plant growth and development by recruiting genetically redundant ABA receptors. To overcome its oxidation inactivation, we developed a novel ABA analog named 2',3'-benzo-iso-ABA (iso-PhABA) and studied its function and structural characterization with A. thaliana ABA receptors. The (+)-iso-PhABA form showed much higher ABA-like activities than (+)-ABA including inhibitory effects on the seed germination of lettuce and A. thaliana, wheat embryo germination and rice seedling elongation. The PP2C (protein phosphatases 2C) activity assay showed that (+)-iso-PhABA acted as a potent and selective ABA receptor agonist, which is preferred to PYL10. In some cases, (-)-iso-PhABA showed moderate to high activity for the PYL protein inhibiting PP2C activity, suggesting different mechanisms of action of iso-PhABA and ABA. The complex crystal structure of iso-PhABA with PYL10 was determined and elucidated successfully, revealing that (+)-iso-PhABA was better coordinated in the same binding pocket compared to (+)-ABA. Moreover, the detailed interaction network of iso-PhABA/PYL10 was disclosed and involves hydrogen bonds and multiple hydrophobic interactions that provide a robust framework for the design of novel ABA receptor agonists/antagonists.
authors.affiliation: College of Science, China Agricultural University, Beijing, 100193, China.|College of Agricultural, Shihezi University, Shihezi, 832000, China.
authors.forename: Xiaoqiang
authors.initials: X
authors.lastname: Han
authors.affiliation: College of Biological Sciences, China Agricultural University, Beijing, 100193, China.|Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing, 100193, China.
authors.forename: Lun
authors.initials: L
authors.lastname: Jiang
authors.affiliation: College of Science, China Agricultural University, Beijing, 100193, China.
authors.forename: Chuanliang
authors.initials: C
authors.lastname: Che
authors.affiliation: College of Science, China Agricultural University, Beijing, 100193, China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Wan
authors.affiliation: College of Science, China Agricultural University, Beijing, 100193, China.
authors.forename: Huizhe
authors.initials: H
authors.lastname: Lu
authors.affiliation: College of Science, China Agricultural University, Beijing, 100193, China.
authors.forename: Yumei
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: College of Science, China Agricultural University, Beijing, 100193, China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Xu
authors.affiliation: College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
authors.forename: Zhongzhou
authors.initials: Z
authors.lastname: Chen
authors.affiliation: College of Science, China Agricultural University, Beijing, 100193, China.
authors.forename: Zhaohai
authors.initials: Z
authors.lastname: Qin
mesh_terms: D000040:Abscisic Acid / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D017360:Arabidopsis / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000819:agonists / Q000737:chemistry / Q000378:metabolism; D018360:Crystallography, X-Ray; D015195:Drug Design; D018525:Germination / Q000187:drug effects; D018545:Lactuca / Q000254:growth & development; D008956:Models, Chemical; D015394:Molecular Structure; D012275:Oryza / Q000254:growth & development; D010937:Plant Growth Regulators / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D000071636:Protein Phosphatase 2C / Q000037:antagonists & inhibitors / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000819:agonists / Q000737:chemistry / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development; D012639:Seeds / Q000187:drug effects / Q000254:growth & development
chemical_list: D029681:Arabidopsis Proteins; C560427:PYL10 protein, Arabidopsis; D010937:Plant Growth Regulators; D011956:Receptors, Cell Surface; D000040:Abscisic Acid; D000071636:Protein Phosphatase 2C