| Autor: |
Haske, Taraneh N., DeBlasi, Antonio, LeVine, Harry |
| Zdroj: |
Journal of Biological Chemistry; February 1996, Vol. 271 Issue: 6 p2941-2948, 8p |
| Abstrakt: |
Cleavage after lysine 32 in the Gγ2subtype and after lysine 36 in the Gγ3subtype 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 Gαo/GαiADP-ribosylation, or its ability to inhibit forskolin-stimulated platelet adenylate cyclase. The Gβsubunit 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. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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