Localization of Gts1p in cortical actin patches of yeast and its possible role in endocytosis.
Herein we report that Gts1p fused with green-fluorescent protein (GFP) is localized in the cortical actin patch besides nuclei in yeast and the cortical Gts1p changed its position together with the patch depending on the cell-cycle phase, while nuclear Gts1p accumulated predominantly in the budding phase. Whereas Gts1p does not directly bind to actin, it associated mainly with the actin-associated protein Pan1p. In the GTS1-deleted transformant gts1Delta, the number of cells containing either a fragmented vacuole or an enlarged single central vacuole increased and the uptake of the hydrophilic dye Lucifer yellow (LY) in the vacuole decreased. Further, gts1Delta transformed with a mutant Gts1p having two cysteine-to-alanine substitutions in a zinc finger resembling that of GTPase-activating proteins of ADP-ribosylation factors (ARF-GAP) neither recovered the LY uptake unlike gts1Delta transformed with the wild-type GTS1, nor reduced the average size of central vacuoles as much as the latter did. These results suggested that Gts1p in the actin patch is involved in the fluid-phase endocytosis and membrane trafficking for vacuole formation and that the putative ARF-GAP domain in Gts1p plays an important role in these functions.
Yaguchi
So-ichi
S
Department of Biochemistry 2, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan.
Shen
Hua
H
Tsurugi
Kunio
K
D020727:ADP-Ribosylation Factors; D000199:Actins / Q000378:metabolism*; D000595:Amino Acid Sequence; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D004705:Endocytosis / Q000187:drug effects; D020690:GTPase-Activating Proteins; D017353:Gene Deletion; D049452:Green Fluorescent Proteins / Q000378:metabolism; D047468:Immunoprecipitation; D007546:Isoquinolines / Q000378:metabolism; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D021381:Protein Transport / Q000187:drug effects; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism; D053778:Thiazolidines / Q000494:pharmacology; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D014617:Vacuoles / Q000187:drug effects / Q000378:metabolism
D000199:Actins; D019086:Bridged Bicyclo Compounds, Heterocyclic; D020690:GTPase-Activating Proteins; C097841:GTS1 protein, S cerevisiae; D007546:Isoquinolines; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D053778:Thiazolidines; D014157:Transcription Factors; D049452:Green Fluorescent Proteins; C017475:lucifer yellow; D020727:ADP-Ribosylation Factors; C037067:latrunculin A