TY - JOUR
T1 - An intact N terminus of the γ subunit is required for the Gβγ stimulation of rhodopsin phosphorylation by human β-adrenergic receptor kinase-1 but not for kinase binding
AU - Haske, Taraneh N.
AU - DeBlasi, Antonio
AU - LeVine, Harry
N1 - Copyright:
Copyright 2007 Elsevier B.V., All rights reserved.
PY - 1996/2/9
Y1 - 1996/2/9
N2 - Cleavage after lysine 32 in the Gγ2 subtype and after lysine 36 in the Gγ3 subtype of purified mixed brain Gβγ by endoproteinase Lys-C blocks Gβγ-mediated stimulation of phosphorylation of rhodopsin in urea-extracted rod outer segments by recombinant human β-adrenergic receptor kinase (hβARK1) holoenzyme while hβARK1 binding to rod outer segments is partially affected. This treatment does not attenuate the binding of the treated Gβγ to C-terminal fragments of hβARK1 containing the pleckstrin homology domain. Lys-C proteolysis also does not alter the association of the Gβγ with phospholipids, its ability to support pertussis toxin-catalyzed Gα(o)/Gα(i) ADP-ribosylation, or its ability to inhibit forskolin-stimulated platelet adenylate cyclase. The Gβ subunit remains noncovalently associated with the cleaved Gγ fragments. Thus, in addition to recruiting hβARK1 to its receptor substrate, Gγ contributes secondary and/or tertiary structural features to activate the kinase.
AB - Cleavage after lysine 32 in the Gγ2 subtype and after lysine 36 in the Gγ3 subtype of purified mixed brain Gβγ by endoproteinase Lys-C blocks Gβγ-mediated stimulation of phosphorylation of rhodopsin in urea-extracted rod outer segments by recombinant human β-adrenergic receptor kinase (hβARK1) holoenzyme while hβARK1 binding to rod outer segments is partially affected. This treatment does not attenuate the binding of the treated Gβγ to C-terminal fragments of hβARK1 containing the pleckstrin homology domain. Lys-C proteolysis also does not alter the association of the Gβγ with phospholipids, its ability to support pertussis toxin-catalyzed Gα(o)/Gα(i) ADP-ribosylation, or its ability to inhibit forskolin-stimulated platelet adenylate cyclase. The Gβ subunit remains noncovalently associated with the cleaved Gγ fragments. Thus, in addition to recruiting hβARK1 to its receptor substrate, Gγ contributes secondary and/or tertiary structural features to activate the kinase.
UR - http://www.scopus.com/inward/record.url?scp=0030022001&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0030022001&partnerID=8YFLogxK
U2 - 10.1074/jbc.271.6.2941
DO - 10.1074/jbc.271.6.2941
M3 - Article
C2 - 8621684
AN - SCOPUS:0030022001
SN - 0021-9258
VL - 271
SP - 2941
EP - 2948
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 6
ER -