Generation and characterization of temperature-sensitive alleles encoding GPI anchored proteins Psu1 and Dfg502 in Schizosaccharomyces pombe.

Glycosyl-phosphatidylinositol (GPI) anchored proteins are implicated in remodeling of the yeast cell wall during growth and division. Schizosaccharomyces pombe proteins, Psu1 , Dfg501 , and Dfg502 are predicted GPI anchored proteins with likely cell wall modifying activity. Here, we isolated and characterized null and temperature-sensitive alleles that will allow further analysis of the function of these proteins and S. pombe cell wall formation. Our data confirm that Psu1 is necessary for cell separation, maintaining proper cell shape, and viability. Additionally, we found that Dfg501 and Dfg502 share a redundant and essential function necessary for cell separation and viability.

Generation and characterization of temperature-sensitive alleles of the glucanosyltransferase Gas1 in Schizosaccharomyces pombe.

The Schizosaccharomyces pombe Gas family of ß-1,3-glucanosyltransferases modify the cell wall by elongating ß-1,3-glucan chains. While gas1Δ cells are inviable under standard laboratory growth conditions, they are viable in the presence of an osmotic stabilizer. Even under these conditions however, gas1Δ cells are slow-growing and display cell separation and morphology defects. Here, we isolated and characterized two gas1 temperature-sensitive alleles. Our data support that Gas1 is the primary S. pombe ß-1,3-glucanosyltransferase important for cell separation and cell viability and provide useful tools for further analysis of S. pombe cell wall formation.