Identification of G alpha 11 as the phospholipase C-activating G-protein of turkey erythrocytes.
A 43 kDa phospholipase C-activating protein has been purified previously from turkey erythrocytes and shown to express immunological properties expected of that of the Gq family of G-protein alpha-subunits [Waldo, Boyer, Morris and Harden (1991) J. Biol. Chem. 266, 14217-14225]. Internal amino acid sequence has now been obtained from this protein which shares 50-100% sequence identity with sequences encoded by mammalian G alpha 11 and G alpha q cDNAs. To identify the purified protein unambiguously, it was necessary to compare its amino acid sequence with the sequence encoded by avian G-protein alpha-subunit cDNA. As such, mouse G alpha q was used as a probe to screen turkey brain and fetal-turkey blood cDNA libraries. A full-length cDNA was identified that encodes avian G alpha 11, on the basis of its 96-98% amino acid identity with mammalian G alpha 11. All eight peptides sequenced from the turkey erythrocyte phospholipase C-activating protein are completely contained within the deduced amino acid sequence of the avian G alpha 11 cDNA. Expression of this cDNA in Sf9 cells by using a baculovirus expression system resulted in the production of a 43 kDa protein that reacts strongly with antisera to the Gq family of G-protein alpha-subunits and activated purified avian phospholipase C in an AlF4(-)-dependent manner. Taken together, these results unambiguously identify the protein purified from turkey erythrocytes, on the basis of its capacity to activate avian phospholipase C, as G alpha 11.
Maurice
D H
DH
Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill 27599.
Waldo
G L
GL
Morris
A J
AJ
Nicholas
R A
RA
Harden
T K
TK
D000535:Aluminum / Q000494:pharmacology; D017607:Aluminum Compounds; D000595:Amino Acid Sequence; D000818:Animals; D016367:Baculoviridae / Q000235:genetics; D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004789:Enzyme Activation / Q000187:drug effects; D004912:Erythrocytes / Q000737:chemistry*; D005459:Fluorides / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000032:analysis* / Q000737:chemistry / Q000235:genetics; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D008969:Molecular Sequence Data; D009036:Moths / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D014162:Transfection; D014422:Turkeys / Q000097:blood*; D010738:Type C Phospholipases / Q000097:blood*
D017607:Aluminum Compounds; D011994:Recombinant Proteins; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D004247:DNA; D000535:Aluminum; D010738:Type C Phospholipases; D019204:GTP-Binding Proteins; D005459:Fluorides; C032311:aluminum fluoride