Molecular cloning of human G alpha q cDNA and chromosomal localization of the G alpha q gene (GNAQ) and a processed pseudogene.
G alpha q is the alpha subunit of one of the heterotrimeric GTP-binding proteins that mediates stimulation of phospholipase C beta. We report the isolation and characterization of cDNA clones from a frontal cortex cDNA library encoding human G alpha q. The encoded protein is 359 amino acids long and is identical in all but one amino acid residue to mouse G alpha q. Analysis of human genomic DNA reveals an intronless sequence with strong homology to human G alpha q cDNA. In comparison to G alpha q cDNA, this genomic DNA sequence includes several small deletions and insertions that alter the reading frame, multiple single base changes, and a premature termination codon in the open reading frame, hallmarks of a processed pseudogene. Probes derived from human G alpha q cDNA sequence map to both chromosomes 2 and 9 in high-stringency genomic blot analyses of DNA from a panel of human-rodent hybrid cell lines. PCR primers that selectively amplify the pseudogene sequence generate a product only when DNA containing human chromosome 2 is used as the template, indicating that the authentic G alpha q gene (GNAQ) is located on chromosome 9. Regional localization by FISH analysis places GNAQ at 9q21 and the pseudogene at 2q14.3-q21.
Dong
Q
Q
Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1752, USA. qhd@helix.nih.gov
Shenker
A
A
Way
J
J
Haddad
B R
BR
Lin
K
K
Hughes
M R
MR
McBride
O W
OW
Spiegel
A M
AM
Battey
J
J
D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics*; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary; D019205:GTP-Binding Protein alpha Subunits, Gs / Q000235:genetics*; D006801:Humans; D006822:Hybrid Cells; D051379:Mice; D008969:Molecular Sequence Data; D011544:Pseudogenes / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
D018076:DNA, Complementary; D019205:GTP-Binding Protein alpha Subunits, Gs