title: A VAMP-associated protein, PVA31 is involved in leaf senescence in Arabidopsis.
abstract: VAMP-associated proteins (VAPs) are highly conserved among eukaryotes. Here, we report a functional analysis of one of the VAPs, PVA31, and demonstrate its novel function on leaf senescence in Arabidopsis. The expression of PVA31 is highly induced in senescence leaves, and localizes to the plasma membrane as well as the ARA7-positive endosomes. Yeast two-hybrid analysis demonstrates that PVA31 is interacted with the plasma membrane localized-VAMP proteins, VAMP721/722/724 but not with the endosome-localized VAMPs, VAMP711 and VAMP727, indicating that PVA31 is associated with VAMP721/722/724 on the plasma membrane. Strong constitutive expression of PVA31 under the control of the Cauliflower mosaic virus 35S promoter induces the typical symptom of leaf senescence earlier than WT in normal growth and an artificially induced senescence conditions.　In addition, the marker genes for the SA-mediated signaling pathways, PR-1, is promptly expressed with elicitor application. These data indicate that PVA31-overexpressing plants exhibit the early senescence phenotype in their leaves, and suggest that PVA31 is involved in the SA-mediated programmed cell death process during leaf senescence and PR-protein secretion during pathogen infection in Arabidopsis.
authors.affiliation: a Graduate School of Life and Environmental Sciences; Kyoto Prefectural University ; Kyoto , Japan.
authors.forename: Mie
authors.initials: M
authors.lastname: Ichikawa
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Nakai
authors.forename: Keita
authors.initials: K
authors.lastname: Arima
authors.forename: Sayo
authors.initials: S
authors.lastname: Nishiyama
authors.forename: Tomoko
authors.initials: T
authors.lastname: Hirano
authors.forename: Masa H
authors.initials: MH
authors.lastname: Sato
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D017796:Caulimovirus; D016923:Cell Death; D002462:Cell Membrane / Q000378:metabolism; D016922:Cellular Senescence; D060467:Disease Resistance; D015870:Gene Expression; D008565:Membrane Proteins / Q000378:metabolism*; D010641:Phenotype; D010935:Plant Diseases / Q000821:virology; D018515:Plant Leaves / Q000378:metabolism*; D020156:Salicylic Acid / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; D008565:Membrane Proteins; D020156:Salicylic Acid
keywords: Arabidopsis thaliana; VAMP-associated protein; cell death; intracellular trafficking; leaf senescence; membrane trafficking