title: Vesicle-associated membrane proteins 721 and 722 are required for unimpeded growth of Arabidopsis under ABA application.
abstract: Soluble N-ethylmaleimide sensitive factor attachment protein receptor (SNARE) proteins are core factors in driving vesicle fusion with target membranes, which is critical in eukaryotes having distinct subcellular organelles. Amongst them, vesicle-associated membrane proteins (VAMP) 721 and 722 are involved in plant growth/development and immunity. In the course of stress responses, plants often show retarded growth. The precise mechanism of this retardation is not fully understood. The plant stress hormone abscisic acid (ABA), which can cause growth inhibition, down-regulates VAMP721/722 protein levels but not transcript levels. Enhanced growth inhibition and early depletion of the amount of VAMP721/722 caused by ABA in haploinsufficient VAMP721(+/-)VAMP722(-/-) and VAMP721(-/-)VAMP722(+/-) plants suggest that ABA impedes plant growth in part by reducing VAMP721/722 proteins. Since VAMP721/722 are engaged in exocytosis, our data implies that ABA-induced growth retardation may result from diminished secretory activities leading to decreased transport of molecules required for plant growth in the plasma membrane and cell wall.
authors.affiliation: Department of Molecular Biology, BK21 Graduate Program for RNA Biology, Dankook University, Yongin 448-701, Republic of Korea.
authors.forename: Changhyun
authors.initials: C
authors.lastname: Yi
authors.forename: Sohyeon
authors.initials: S
authors.lastname: Park
authors.forename: Hye Sup
authors.initials: HS
authors.lastname: Yun
authors.forename: Chian
authors.initials: C
authors.lastname: Kwon
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D015536:Down-Regulation / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D011499:Protein Processing, Post-Translational / Q000187:drug effects / Q000235:genetics; D050683:R-SNARE Proteins / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D050683:R-SNARE Proteins; C570049:VAMP721 protein, Arabidopsis; C570050:VAMP722 protein, Arabidopsis; D000040:Abscisic Acid