DROSOPHILA RETINAL-DEGENERATION-C (RDGC) ENCODES A NOVEL SERINE THREONINE PROTEIN PHOSPHATASE

The Drosophila retinal degeneration C (rdgC) gene is required to prevent light-induced retinal degeneration. Molecular analysis shows that the rdgC transcription unit encodes a novel serine/threonine protein phosphatase. Amino acids 153-393 define a domain that has 30% identity with the catalytic domains of types 1, 2A, and 2B serine/threonine protein phosphatases. A putative regulatory domain is appended that contains multiple potential Ca2+-binding sites or "EF hand motifs." Thus, the analysis suggests that the rdgC protein is a novel type of serine/threonine protein phosphatase that is directly regulated by Ca2+. rdgC is expressed in the visual systems of the fly, as well as in the mushroom bodies of the central brain.