Inhibition of phosphatidylinositol 3,5-bisphosphate production has pleiotropic effects on various membrane trafficking routes in Arabidopsis.
Phosphoinositides play an important role in various membrane trafficking events in eukaryotes. One of them, however, phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2], has not been studied widely in plants. Using a combination of fluorescent reporter proteins and the PI(3,5)P2-specific inhibitor YM202636, here we demonstrated that in Arabidopsis thaliana, PI(3,5)P2 affects various membrane trafficking events, mostly in the post-Golgi routes. We found that YM201636 treatment effectively reduced PI(3,5)P2 concentration not only in the wild type but also in FAB1A-overexpressing Arabidopsis plants. In particular, reduced PI(3,5)P2 levels caused abnormal membrane dynamics of plasma membrane proteins, AUX1 and BOR1, with different trafficking patterns. Secretion and morphological characteristics of late endosomes and vacuoles were also affected by the decreased PI(3,5)P2 production. These pleiotropic defects in the post-Golgi trafficking events were caused by the inhibition of PI(3,5)P2 production. This effect is probably mediated by the inhibition of maturation of FAB1-positive late endosomes, thereby impairing late endosome function. In conclusion, our results imply that in Arabidopsis, late endosomes are involved in multiple post-Golgi membrane trafficking routes including not only vacuolar trafficking and endocytosis but also secretion.
Laboratory of Cellular Dynamics, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan.
Tomoko
T
Hirano
Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands.
Teun
T
Munnik
Laboratory of Cellular Dynamics, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan.
Masa H
MH
Sato
D000631:Aminopyridines / Q000494:pharmacology; D017920:Antiporters / Q000235:genetics / Q000378:metabolism; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism*; D011992:Endosomes / Q000187:drug effects / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D058685:Genetic Pleiotropy / Q000235:genetics; D006056:Golgi Apparatus / Q000187:drug effects / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006575:Heterocyclic Compounds, 3-Ring / Q000494:pharmacology; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D018613:Microscopy, Confocal; D009154:Mutation; D018129:Phosphatidylinositol Phosphates / Q000037:antagonists & inhibitors / Q000378:metabolism*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D021381:Protein Transport / Q000187:drug effects / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014617:Vacuoles / Q000187:drug effects / Q000378:metabolism
C540576:6-amino-N-(3-(4-(4-morpholinyl)pyrido(3',2'-4,5)furo(3,2-d)pyrimidin-2-yl)phenyl)-3-pyridinecarboxamide; C100794:AUX1 protein, Arabidopsis; D000631:Aminopyridines; D017920:Antiporters; D029681:Arabidopsis Proteins; C469216:BOR1 protein, Arabidopsis; D006575:Heterocyclic Compounds, 3-Ring; D026901:Membrane Transport Proteins; D018129:Phosphatidylinositol Phosphates; C106336:phosphatidylinositol 3,5-diphosphate; D049452:Green Fluorescent Proteins; C547216:FAB1A protein, Arabidopsis; C547217:FAB1B protein, Arabidopsis; D017853:Phosphotransferases (Alcohol Group Acceptor)
Arabidopsis thaliana; FAB1/PIKfyve; Phosphatidylinositol 3,5-bisphosphate; Post-Golgi membrane trafficking routes; YM201636