Transcription of multiple cell wall protein-encoding genes in Saccharomyces cerevisiae is differentially regulated during the cell cycle.

The yeast cell wall consists of an internal skeletal layer and an outside protein layer. The synthesis of both beta-1,3-glucan and chitin, which together from the cell wall skeleton, is cell cycle-regulated. We show here that the expression of five cell wall protein-encoding genes (CWP1, CWP2, SED1, TIP1 and TIR1) is also cell cycle-regulated. TIP1 is expressed in G1 phase, CWP1, CWP2 and TIR1 are expressed in S/G2 phase, and SED1 in M phase. The data suggest that these proteins fulfil distinct functions in the cell wall.