Quantitation and significance of 125I-calmodulin binding to myosin light chain kinase and phosphorylase distributed on polyacrylamide gels.
Journal Article (Journal Article)
Glycogen phosphorylase (a or b) binds 125I-calmodulin in a Ca2+-dependent manner, in the 125I-calmodulin overlay technique. This binding is quantitatively identical to 125I-calmodulin binding to myosin light chain kinase. In an in vitro assay, calmodulin stimulates phosphorylase activity at limiting concentrations of either glucose-1-phosphate or glycogen, but the Ka is 1000 fold higher than for the kinase, and is not Ca2+-dependent. Activation of phosphorylase, but not myosin light chain kinase, by calmodulin can be mimicked by troponin C or bovine serum albumin. These results demonstrate that the properties of calmodulin interaction with proteins can vary between the 125I-calmodulin technique and a functional assay of calmodulin effect on the same protein.
Full Text
Duke Authors
Cited Authors
- Slaughter, GR; Means, AR
Published Date
- January 16, 1985
Published In
Volume / Issue
- 126 / 1
Start / End Page
- 295 - 303
PubMed ID
- 3918530
International Standard Serial Number (ISSN)
- 0006-291X
Digital Object Identifier (DOI)
- 10.1016/0006-291x(85)90605-9
Language
- eng
Conference Location
- United States