The regulation ofcAMP levels by protein-tyrosine phosphorylation
Abstract
The goal of this project was to gain insight into the modulation of cAMP levels by crosstalk with protein-tyrosine kinase (PTK) signaling pathways. We have obtained evidence that tyrosine phosphorylation increases the activity of adenylyl cyclase. The general PTK inhibitors, genistein and herbimycin A, decreased cAMP production by 40–60%. This inhibition was observed when adenylyl cyclase was activated by either G-protein coupled receptors or directly with forskolin. Additionally, inhibition of protein-tyrosine phosphatases with vanadate dramatically enhanced cAMP production. Further investigation of these effects were continued in S49 wild type, S49 cyc-, and Sf9 cells, providing evidence that adenylyl cyclase may be the substrate for tyrosine phosphorylation and that the regulation of cAMP by proteintyrosine phosphorylation is not limited to HT4.7 cells. In order to aid the study of the post-translational modifications of adenylyl cyclase, an antibody recognizing the enzyme was produced and its characterization is presented here.
Degree
Ph.D.
Advisors
Morimoto, Purdue University.
Subject Area
Biochemistry|Molecular biology
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