The mouse glucocorticoid receptor DNA-binding domain is not phosphorylated in vivo |
| |
Authors: | W S van der Weijden Benjamin W J Hendry R W Harrison |
| |
Affiliation: | Division of Endocrinology/Metabolism, University of Arkansas for Medical Sciences, Little Rock 72207. |
| |
Abstract: | The glucocorticoid receptor is phosphorylated, but the precise location of the phosphorylated groups is unknown. We cultured AtT-20 cells in medium containing [32P]-orthophosphate and used immunoaffinity methods to isolate the intact receptor and a tryptic fragment containing the DNA binding domain. Analysis of the intact receptor, co-labeled with the affinity ligand dexamethasone-mesylate, confirmed that the receptor was phosphorylated. Isolation of the DNA binding domain by trypsinization and immunopurification showed that it was not phosphorylated. Interestingly, a non-immunoreactive phosphorylated fragment similar in size to the DNA-binding fragment was observed. Our results suggest that phosphorylation of the DNA binding domain of the glucocorticoid receptor is not essential for hormone action. |
| |
Keywords: | |
|
|