Modified vacuole phenotype1 is an arabidopsis myrosinase-associated protein involved in endomembrane protein trafficking

April E. Agee, Marci Surpin, Eun Ju Sohn, Thomas Girke, Abel Rosado, Brian W. Kram, Clay J Carter, Adam M. Wentzell, Daniel J. Kliebenstein, Hak Chul Jin, Ohkmae K. Park, Hailing Jin, Glenn R. Hicks, Natasha V. Raikhel

Research output: Contribution to journalArticlepeer-review

56 Scopus citations


We identified an Arabidopsis (Arabidopsis thaliana) ethyl methanesulfonate mutant, modified vacuole phenotype1-1 (mvp1-1), in a fluorescent confocal microscopy screen for plants with mislocalization of a green fluorescent protein-δ tonoplast intrinsic protein fusion. The mvp1-1 mutant displayed static perinuclear aggregates of the reporter protein. mvp1 mutants also exhibited a number of vacuole-related phenotypes, as demonstrated by defects in growth, utilization of stored carbon, gravitropic response, salt sensitivity, and specific susceptibility to the fungal necrotroph Alternaria brassicicola. Similarly, crosses with other endomembrane marker fusions identified mislocalization to aggregate structures, indicating a general defect in protein trafficking. Map-based cloning showed that the mvp1-1 mutation altered a gene encoding a putative myrosinase-associated protein, and glutathione S-transferase pull-down assays demonstrated that MVP1 interacted specifically with the Arabidopsis myrosinase protein, THIOGLUCOSIDE GLUCOHYDROLASE2 (TGG2), but not TGG1. Moreover, the mvp1-1 mutant showed increased nitrile production during glucosinolate hydrolysis, suggesting that MVP1 may play a role in modulation of myrosinase activity. We propose that MVP1 is a myrosinase-associated protein that functions, in part, to correctly localize the myrosinase TGG2 and prevent inappropriate glucosinolate hydrolysis that could generate cytotoxic molecules.

Original languageEnglish (US)
Pages (from-to)120-132
Number of pages13
JournalPlant physiology
Issue number1
StatePublished - Jan 2010


Dive into the research topics of 'Modified vacuole phenotype1 is an arabidopsis myrosinase-associated protein involved in endomembrane protein trafficking'. Together they form a unique fingerprint.

Cite this