title: Wortmannin treatment induces changes in Arabidopsis root proteome and post-Golgi compartments.
abstract: Wortmannin is a widely used pharmaceutical compound which is employed to define vesicular trafficking routes of particular proteins or cellular compounds. It targets phosphatidylinositol 3-kinase and phosphatidylinositol 4-kinases in a dose-dependent manner leading to the inhibition of protein vacuolar sorting and endocytosis. Combined proteomics and cell biological approaches have been used in this study to explore the effects of wortmannin on Arabidopsis root cells, especially on proteome and endomembrane trafficking. On the subcellular level, wortmannin caused clustering, fusion, and swelling of trans-Golgi network (TGN) vesicles and multivesicular bodies (MVBs) leading to the formation of wortmannin-induced multivesicular compartments. Appearance of wortmannin-induced compartments was associated with depletion of TGN as revealed by electron microscopy. On the proteome level, wortmannin induced massive changes in protein abundance profiles. Wortmannin-sensitive proteins belonged to various functional classes. An inhibition of vacuolar trafficking by wortmannin was related to the downregulation of proteins targeted to the vacuole, as showed for vacuolar proteases. A small GTPase, RabA1d, which regulates vesicular trafficking at TGN, was identified as a new protein negatively affected by wortmannin. In addition, Sec14 was upregulated and PLD1 alpha was downregulated by wortmannin.
authors.affiliation: Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Cell Biology, Faculty of Science, Palacký University , Šlechtitelů 11, CZ-783 71 Olomouc, Czech Republic.
authors.forename: Tomáš
authors.initials: T
authors.lastname: Takáč
authors.forename: Tibor
authors.initials: T
authors.lastname: Pechan
authors.forename: Olga
authors.initials: O
authors.lastname: Samajová
authors.forename: Miroslav
authors.initials: M
authors.lastname: Ovečka
authors.forename: Hendrik
authors.initials: H
authors.lastname: Richter
authors.forename: Carola
authors.initials: C
authors.lastname: Eck
authors.forename: Karsten
authors.initials: K
authors.lastname: Niehaus
authors.forename: Jozef
authors.initials: J
authors.lastname: Samaj
mesh_terms: D000730:Androstadienes / Q000494:pharmacology*; D017360:Arabidopsis / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D057146:Multivesicular Bodies / Q000187:drug effects / Q000378:metabolism; D010739:Phospholipase D / Q000378:metabolism; D049294:Phospholipid Transfer Proteins / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D021381:Protein Transport / Q000187:drug effects; D020543:Proteome / Q000378:metabolism*; D000077191:Wortmannin; D020691:rab GTP-Binding Proteins / Q000378:metabolism; D021601:trans-Golgi Network / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D000730:Androstadienes; D029681:Arabidopsis Proteins; D049294:Phospholipid Transfer Proteins; D020543:Proteome; D010739:Phospholipase D; C106801:phospholipase D1; D020691:rab GTP-Binding Proteins; D000077191:Wortmannin