Overexpression of Sna3 stabilizes tryptophan permease Tat2, potentially competing for the WW domain of Rsp5 ubiquitin ligase with its binding protein Bul1.
Tryptophan permease Tat2 in Saccharomyces cerevisiae undergoes Rsp5-dependent degradation upon exposure to high hydrostatic pressure and it limits the growth of tryptophan auxotrophs. Overexpression of SNA3 encoding an endosomal/vacuolar protein possessing the PPAY motif allowed growth at 25 MPa, which was potentiated by marked stabilization of Tat2. This appeared to depend on the PPAY motif, which interacted with the WW domain of Rsp5. Subcellular localization of Rsp5 was unchanged by overexpression of either SNA3 or SNA3-AAAY. While the loss of Bul1, a binding protein of Rsp5, or the rsp5-ww3 mutation allowed high-pressure growth, overexpression of BUL1 abolished the Sna3-mediated growth at 25 MPa. These results suggest that Sna3 and Bul1 compete for the WW domain of Rsp5 upon Tat2 ubiquitination.
Hiraki
Toshiki
T
Molecular Evolution and Adaptation Research, Institute of Biogeosciences, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan.
Abe
Fumiyoshi
F
D026905:Amino Acid Transport Systems / Q000378:metabolism*; D001667:Binding, Competitive; D056827:Endosomal Sorting Complexes Required for Transport / Q000235:genetics / Q000378:metabolism*; D004795:Enzyme Stability; D006874:Hydrostatic Pressure; D008565:Membrane Proteins / Q000096:biosynthesis*; D017434:Protein Structure, Tertiary / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism*; D014364:Tryptophan / Q000378:metabolism; D043743:Ubiquitin-Protein Ligase Complexes / Q000235:genetics / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*; D054875:Ubiquitination
D026905:Amino Acid Transport Systems; C099939:BUL1 protein, S cerevisiae; D056827:Endosomal Sorting Complexes Required for Transport; D008565:Membrane Proteins; D029701:Saccharomyces cerevisiae Proteins; C437323:Sna3 protein, S cerevisiae; C429825:TAT2 protein, S cerevisiae; D014364:Tryptophan; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases; C469287:RSP5 protein, S cerevisiae