Phospholipase D and the SNARE Sso1p are necessary for vesicle fusion during sporulation in yeast.
Spore formation in Saccharomyces cerevisiae requires the de novo formation of prospore membranes. The coalescence of secretory vesicles into a membrane sheet occurs on the cytoplasmic surface of the spindle pole body. Spo14p, the major yeast phospholipase D, is necessary for prospore membrane formation; however, the specific function of Spo14p in this process has not been elucidated. We report that loss of Spo14p blocks vesicle fusion, leading to the accumulation of prospore membrane precursor vesicles docked on the spindle pole body. A similar phenotype was seen when the t-SNARE Sso1p, or the partially redundant t-SNAREs Sec9p and Spo20p were mutated. Although phosphatidic acid, the product of phospholipase D action, was necessary to recruit Spo20p to the precursor vesicles, independent targeting of Spo20p to the membrane was not sufficient to promote fusion in the absence of SPO14. These results demonstrate a role for phospholipase D in vesicle fusion and suggest that phospholipase D-generated phosphatidic acid plays multiple roles in the fusion process.
Department of Biochemistry and Cell Biology, SUNY Stony Brook, Stony Brook, NY 4-5215, USA.
Hideki
H
Nakanishi
Masayo
M
Morishita
Cindi L
CL
Schwartz
Alison
A
Coluccio
JoAnne
J
Engebrecht
Aaron M
AM
Neiman
D015153:Blotting, Western; D005456:Fluorescent Dyes; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007211:Indoles; D008856:Microscopy, Fluorescence; D018715:Microscopy, Video; D008954:Models, Biological; D009154:Mutation; D010739:Phospholipase D / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D050765:Qa-SNARE Proteins / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D022142:Secretory Vesicles / Q000378:metabolism* / Q000648:ultrastructure; D013172:Spores, Fungal / Q000378:metabolism* / Q000648:ultrastructure; D013696:Temperature; D014054:Tomography
D005456:Fluorescent Dyes; D007211:Indoles; D050765:Qa-SNARE Proteins; C084006:SSO1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D049452:Green Fluorescent Proteins; C007293:DAPI; D010739:Phospholipase D