Multiple pathways regulate endocytic coat disassembly in Saccharomyces cerevisiae for optimal downstream trafficking.
Recently, a pathway involving the highly choreographed recruitment of endocytic proteins to sites of clathrin/actin-mediated endocytosis has been revealed in budding yeast. Here, we investigated possible roles for candidate disassembly factors in regulation of the dynamics of the endocytic coat proteins Sla2p, Ent1p, Ent2p, Sla1p, Pan1p and End3p, each of which has mammalian homologues. Live cell imaging analysis revealed that in addition to the synaptojanin, Sjl2p, the Ark1p and Prk1p protein kinases, the putative Arf GTPase-activating protein, Gts1p and the Arf GTPase-interacting protein, Lsb5p, also arrive at endocytic sites late in the internalization pathway, consistent with roles in coat disassembly. Analysis of coat dynamics in various mutant backgrounds revealed that multiple pathways, including the ones mediated by an Arf guanosine triphosphatase and a synaptojanin, facilitate efficient disassembly of different endocytic coat proteins. In total, at least four separate processes are important for disassembly of endocytic complexes and efficient downstream trafficking of endocytic cargo.
Toret
Christopher P
CP
Department of Molecular and Cell Biology, University of California, 16 Barker Hall, Berkeley, CA 94720-3202, USA.
Lee
Linda
L
Sekiya-Kawasaki
Mariko
M
Drubin
David G
DG
D020727:ADP-Ribosylation Factors / Q000235:genetics / Q000378:metabolism; D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism; D033942:Adaptor Proteins, Vesicular Transport / Q000235:genetics / Q000378:metabolism; D000818:Animals; D034021:Auxilins / Q000235:genetics / Q000378:metabolism; D036022:Capsid Proteins / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D004705:Endocytosis / Q000502:physiology*; D011992:Endosomes / Q000378:metabolism*; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism*
D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D034021:Auxilins; D036022:Capsid Proteins; D002352:Carrier Proteins; C121319:ENT1 protein, S cerevisiae; C121321:ENT2 protein, S cerevisiae; C475127:Lsb5 protein, S cerevisiae; D008840:Microfilament Proteins; D009419:Nerve Tissue Proteins; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins; C114154:epsin; C491504:ARK1 protein, S cerevisiae; C094326:PRK1 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; C097702:synaptojanin; D010744:Phosphoric Monoester Hydrolases; C492128:ARF3 protein, S cerevisiae; D020727:ADP-Ribosylation Factors