Endogenous protein inhibitor of mitochondrial c-AMP phosphodiesterase in tumour bearing rats
Sankaran, K.
Indian Journal of Biochemistry and Biophysics 23(2): 66-69
1986
ISSN/ISBN: 0301-1208 PMID: 3021610 Document Number: 279783
A heat-stable protein inhibiting the calmodulin-dependent activation of c-AMP phosphodiesterase (PDE) has been purified to homogeneity from liver mitochondria of Yoshida ascites tumour bearing rats, by heating the soicated mitochondrial extract at 90.degree.C followed by DEAE-cellulose chromatography and gel filtration on Sephadex G-100. Protein nature of this inhibitor was ascertained by its susceptibility to trypsin. The purified inhibitor showed a single band on polyacrylamide gel electrophoresis and had an apparent molecular weight of 26,000. This inhibitor protein was observed to counteract the activation of the purified host liver mitochondrial c-AMP PDE by calmodulin without affecting the basal activity.