We have examined the developmental regulation and function of two Gα protein subunits, Gα1 and Gα2, from Dictyostelium. Gα1 is expressed in vegetative cells through aggregate stages while Gα2 is inducible by cAMP pulses and preferentially expressed in aggregation. Our results suggest that Gα2 encodes the Gα protein subunit associated with the cAMP receptor and mediates all known receptor-activated intracellular signal transduction processes, including chemotaxis and gene regulation. Gα1 appears to function in both the cell cycle and development. Overexpression of Gα1 results in large, multinucleated cells that develop abnormally. The central role that these Gα proteins play in signal transduction processes and in controlling Dictyostelium development is discussed.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)