ISSN:
0021-9541
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
The protein kinase C stimulator TPA (12-0-tetradecanoyl phorbol-13-acetate) enhanced the responsiveness of adenylate cyclase to IPR (isoproterenol) and PGE1 (prostaglandin E1) in quiescent tsKSV-NRK cells at the nonpermissive 41°C Reactivating the thermolabile mitogenic/oncogenic K-ras protein in tsKSV-NRK cells by dropping the temperature to 36°C also enhanced the responsiveness of adenylate cyclase to IPR and PGE1. The enhancement was transient and peaked at 6 hours after the temperature shift. This enhanced the responsiveness was specifically due to the reactivated viral K-ras protein rather than the temperature shift because the same temperature shift did not affect adenylate cyclase responsiveness in uninfected NRK cells, nor was it a result of the mitogenic stimulus since reactivating the mitogenic pp60v-src protein in tsASV-NRK cells did not affect adenylate cyclase responsiveness. The increased responsiveness of adenylate cyclase at 6 hours after the temperature shift was not a result of elevated membrane-associated PKC activity. However, the reactivated viral K-ras protein strongly increased the stimulability of membrane-associated PKC by TPA and it further increased TPA's ability to enhance the responsiveness of adenylate cyclase to IPR and PGE1. Thus, a viral K-ras protein and membrane-associated protein kinase C can cooperate to increase the responsiveness of adenylate cyclase to agonists.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcp.1041400302
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