Proteins with a Vps9 domain function as guanine nucleotide exchange factors for Rab proteins and can mediate the uptake of cell surface receptors or other molecules through endocytosis. However, genes encoding these proteins have not been previously studied in cells with robust chemotactic
capabilities. Several genes encoding Vps9 domains were identified in the genome of Dictyostelium discoideum, and one of the genes, designated as rgfA (DDB_G0272038), was examined for functions in cell growth, development, and chemotaxis. The rgfA gene was expressed during
vegetative growth and throughout development, but disruption of this gene resulted in no major alterations in cell growth, macropinocytosis, developmental morphology, or chemotactic movement. However, heterologous expression of RgfA resulted in a delay of developmental morphogenesis and impaired
chemotaxis of cells to folate but did not affect macropinocytosis. These results suggest that RgfA might share redundant functions with other Dictyostelium Vps9-domain proteins and that heterologous expression of this protein can alter processes that depend on the reception of external
Published since 1954, this monthly journal contains new research in the field of microbiology including applied microbiology and biotechnology; microbial structure and function; fungi and other eucaryotic protists; infection and immunity; microbial ecology; physiology, metabolism and enzymology; and virology, genetics, and molecular biology. It also publishes review articles and notes on an occasional basis, contributed by recognized scientists worldwide.