RRC ID 45514
Author Ishida M, Ohbayashi N, Maruta Y, Ebata Y, Fukuda M.
Title Functional involvement of Rab1A in microtubule-dependent anterograde melanosome transport in melanocytes.
Journal J Cell Sci
Abstract Melanosomes are transported to the cell periphery of melanocytes by coordination between bidirectional microtubule-dependent movements and unidirectional actin-dependent movement. Although both the mechanism of the actin-dependent melanosome transport and the mechanism of the microtubule-dependent retrograde melanosome transport in mammalian skin melanocytes have already been determined, almost nothing is known about the mechanism of the microtubule-dependent anterograde melanosome transport. Small GTPase Rab proteins are common regulators of membrane traffic in all eukaryotes, and in this study we performed genome-wide screening for Rab proteins that are involved in anterograde melanosome transport by expressing 60 different constitutive active (and negative) mutants, and succeeded in identifying Rab1A, originally described as a Golgi-resident Rab, as a prime candidate. Endogenous Rab1A protein was found to be localized to mature melanosomes in melanocytes, and its functional ablation either by siRNA-mediated knockdown or by overexpression of a cytosolic form of Rab1A-GTPase-activating protein/TBC1D20 induced perinuclear melanosome aggregation. The results of time-lapse imaging further revealed that long-range anterograde melanosome movements were specifically suppressed in Rab1A-deficient melanocytes, whereas retrograde melanosome transport occurred normally. Taken together, these findings indicate that Rab1A is the first crucial component of the anterograde melanosome transport machinery to be identified in mammalian skin melanocytes.
Volume 125(Pt 21)
Pages 5177-87
Published 2012-11-1
DOI 10.1242/jcs.109314
PII jcs.109314
PMID 22854043
MeSH Animals Cell Line Gene Knockdown Techniques Green Fluorescent Proteins / metabolism Humans Melanocytes / enzymology* Melanosomes / enzymology* Mice Microscopy, Fluorescence Microtubules / metabolism* Mutagenesis, Site-Directed Mutation, Missense Protein Isoforms / metabolism Protein Transport RNA, Small Interfering / genetics rab1 GTP-Binding Proteins / genetics rab1 GTP-Binding Proteins / metabolism*
IF 4.517
Times Cited 29
DNA material pEGFPC1-mouse Rab8A-Q67L - constitutive active (RDB14275) pEGFPC1-mouse Rab8A-T22N - constitutive negative (RDB14276) pEGFPC1-mouse Rab10-Q68L - constitutive active (RDB14277) pEGFPC1-mouse Rab10-T23N - constitutive negative (RDB14278) pEGFP-C1-mouse Rab29-Q67L (RDB14975) pEGFP-C1-mouse Rab29-T21N (RDB14976) pEGFP-C1-mouse Rab5A-Q79L (RDB15726) pEGFP-C1-mouse Rab20(R59L) (RDB15732) pEGFP-C1-mouse Rab5C(Q80L) (RDB15733) pEGFP-C1-mouse Rab32(Q83L) (RDB15734) pEGFP-C1-mouse Rab34(111L) (RDB15735) pEGFP-C1-Rab41-T30N (RDB15977) pEGFP-C1-Rab41-Q75L (RDB15978) pEGFP-C1-Rab1A-S25N (RDB16866) pEGFP-C1-Rab1A-Q70L (RDB16867) pEGFP-Rab2A-S20N (RDB16868) pEGFP-C1-Rab2A-Q65L (RDB16869) pEGFP-C1-Rab3A-T36N (RDB16870) pEGFP-C1-Rab3A-Q81L (RDB16871) pEGFP-C1-Rab4A-S27N (RDB16872) pEGFP-C1-Rab4A-Q72L (RDB16873) pEGFP-C1-Rab5A-S34N (RDB16874) pEGFP-C1-Rab6A-T27N (RDB16875) pEGFP-C1-Rab6A-Q72L (RDB16876) pEGFP-C1-Rab7-T22N (RDB16877) pEGFP-C1-Rab7-Q67L (RDB16878) pEGFP-C1-Rab9A-S21N (RDB16879) pEGFP-C1-Rab9A-Q66L (RDB16880) pEGFP-C1-Rab12-T55N (RDB16881) pEGFP-C1-Rab12-Q100L (RDB16882) pEGFP-C1-Rab17-T33N (RDB16883) pEGFP-C1-Rab17-Q77L (RDB16884) pEGFP-C1-Rab20-T19N (RDB16885) pEGFP-C1-Rab21-T31N (RDB16886) pEGFP-C1-Rab21-Q76L (RDB16887) pEGFP-C1-Rab27A-T23N (RDB16888) pEGFP-C1-Rab27A-Q78L (RDB16889) pEGFP-C1-Rab32-T37N (RDB16890) pEGFP-C1-Rab33A-T50N (RDB16891) pEGFP-C1-Rab33A-Q95L (RDB16892) pEGFP-C1-Rab35-S22N (RDB16893) pEGFP-C1-Rab35-Q67L (RDB16894) pEGFP-C1-Rab36-T71N (RDB16895) pEGFP-C1-Rab36-Q116L (RDB16896) pEGFP-C1-Rab37-T43N (RDB16897) pEGFP-C1-Rab37-Q89L (RDB16898) pEGFP-C1-Rab38-T23N (RDB16899) pEGFP-C1-Rab38-Q69L (RDB16900) pEGFP-C1-Rab40C-G28N (RDB16901) pEGFP-C1-Rab40C-Q73L (RDB16902)