Functional heterogeneity of transducin alpha subunits.
The N-terminal glycine of transducin alpha subunits is acylated by lauroyl (C12:0), myristoyl (C14:0), (cis-delta5)-tetradecaenoyl (C14:1) or (cis,cis-delta5,delta8)-tetradecadienoyl (C14:2) fatty acyl groups. We examined functional heterogeneity of transducin by sequentially eluting it from bleached outer segments using increasing concentrations of GTP then identifying the N-terminal acyl groups on the eluted alpha subunits. C14:2 acylated transducin eluted at low GTP concentrations followed by C12:0, C14:1 and C14:0 transducin at higher GTP concentrations. This suggests functional heterogeneity in the different forms of transducin alpha subunits.
Neubert
T A
TA
Department of Biochemistry and Howard Hughes Medical Institute, University of Washington School of Medicine, Seattle 98195, USA.
Hurley
J B
JB
D000107:Acetylation; D000818:Animals; D002417:Cattle; D002853:Chromatography, Liquid; D006160:Guanosine Triphosphate / Q000378:metabolism; D006868:Hydrolysis; D013058:Mass Spectrometry; D012374:Rod Cell Outer Segment / Q000737:chemistry; D013329:Structure-Activity Relationship; D015293:Transducin / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*
D006160:Guanosine Triphosphate; D015293:Transducin