Comparison of substrate recognition by protein kinase C (type III) between rat liver cytosolic and particulate fractions |
| |
Authors: | E Hashimoto H Yamamura |
| |
Institution: | Department of Biochemistry, Fukui Medical School, Japan. |
| |
Abstract: | 1. Phosphorylation of rat liver endogenous substrates by protein kinase C (type III) was compared between cytosolic and particulate (mitochondria, microsomes and plasma membrane) fractions. 2. The rate and the maximum level of protein phosphorylation were several-fold higher in particulate fractions than in cytosolic fraction. 3. Protein phosphorylation in cytosolic fraction was dependent on both Ca2+ and phospholipid, but only Ca2+ was necessary in phosphorylation of particulate fractions. 4. These results suggest that protein kinase C (type III) has much more target proteins in particulate fractions rather than in cytosolic fraction and Ca2+ was important regulator in particulate protein phosphorylation. |
| |
Keywords: | |
|
|