SUMMARY PARAGRAPH for PLP2
PLP2 is one of two S. cerevisiae genes encoding proteins similar to mammalian phosducins (1). Phosducins inhibit the GTPase activity of several heterotrimeric G proteins, presumably as a consequence of binding to the beta-gamma subunits of the G proteins (5, 6).
Plp2p is essential for viability, but the other phosducin-related protein, Plp1p, is not (1). In yeast, a heterotrimeric G protein comprising Gpa1p, Ste4p, and Ste18p transduces the mating pheromone signal (reviewed in reference 7). Both Plp1p and Plp2p bind to the yeast G beta-gamma complex (Ste4p and Ste18p), suggesting that they may play a role in mating pheromone signal transduction (1). Overexpression of PLP1 or PLP2 reduces pheromone-responsive transcriptional activation, but has no effect on pheromone induced growth arrest (1). Deletion of STE7, which encodes a MAP kinase kinase involved in pheromone signal transduction downstream of the heterotrimeric G protein (7) does not rescue the plp2 null mutant, suggesting that Plp2p may have an essential role in a process other than mating (1).
Last updated: 2000-04-13