Evidence that the RdeA protein is a component of a multistep phosphorelay modulating rate of development in Dictyostelium.
We have isolated an insertional mutant of Dictyostelium discoideum that aggregated rapidly and formed spores and stalk cells within 14 h of development instead of the normal 24 h. We have shown by parasexual genetics that the insertion is in the rdeA locus and have cloned the gene. It encodes a predicted 28 kDa protein (RdeA) that is enriched in charged residues and is very hydrophilic. Constructs with the DNA for the c-Myc epitope or for the green fluorescent protein indicate that RdeA is not compartmentalized. RdeA displays homology around a histidine residue at amino acid 65 with members of the H2 module family of phosphotransferases that participate in multistep phosphoryl relays. Replacement of this histidine rendered the protein inactive. The mutant is complemented by transformation with the Ypd1 gene of Saccharomyces cerevisiae, itself an H2 module protein. We propose that RdeA is part of a multistep phosphorelay system that modulates the rate of development.
Chang
W T
WT
Department of Biochemistry, University of Oxford, Oxford, UK.
Thomason
P A
PA
Gross
J D
JD
Neweil
P C
PC
D000262:Adenylyl Cyclases / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004023:Dictyostelium / Q000254:growth & development* / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D016296:Mutagenesis; D011494:Protein Kinases; D015800:Protozoan Proteins; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D047908:Intracellular Signaling Peptides and Proteins; D015800:Protozoan Proteins; C112741:RdeA protein, Dictyostelium; D029701:Saccharomyces cerevisiae Proteins; D011494:Protein Kinases; C102035:YPD1 protein, S cerevisiae; D000262:Adenylyl Cyclases