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Multiple alpha subunits of guanine nucleotide-binding proteins in Dictyostelium.

ABSTRACT: Previous results have shown that chemotaxis and the expression of several classes of genes in Dictyostelium discoideum are regulated through a cell surface cAMP receptor interacting with guanine nucleotide-binding proteins (G proteins). We now describe cloning and sequencing of cDNAs encoding two G alpha protein subunits from Dictyostelium. The derived amino acid sequences show that they are 45% identical to each other and to G alpha protein subunits from mammals and yeast. Both cDNAs are complementary to multiple mRNAs that are differentially expressed during development. This evidence and analysis of mutants presented elsewhere suggest that they have distinct physiological functions.

SUBMITTER: Pupillo M

PROVIDER: S-EPMC297521 | biostudies-other | 1989 Jul

REPOSITORIES: biostudies-other

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Multiple alpha subunits of guanine nucleotide-binding proteins in Dictyostelium.

Pupillo M M Kumagai A A Pitt G S GS Firtel R A RA Devreotes P N PN

Proceedings of the National Academy of Sciences of the United States of America 19890701 13

Previous results have shown that chemotaxis and the expression of several classes of genes in Dictyostelium discoideum are regulated through a cell surface cAMP receptor interacting with guanine nucleotide-binding proteins (G proteins). We now describe cloning and sequencing of cDNAs encoding two G alpha protein subunits from Dictyostelium. The derived amino acid sequences show that they are 45% identical to each other and to G alpha protein subunits from mammals and yeast. Both cDNAs are comple ...[more]

PMID: 2500658

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