Expression in Escherichia coli and phosphorylation with cAMP-dependent protein kinase of the N-terminal region of human endothelial actin-binding protein.

The N-terminal region of human endothelial actin-binding protein was subcloned and expressed in the pT 7-7/E. coli BL 21 (DE 3) system. This peptide was efficiently expressed in E. coli as indicated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by western analysis using a monoclonal antibody raised against this part of the molecule. As predicted by the amino acid sequence this truncated protein (residues 21-1569), corresponding to 164 KD and containing the actin-binding domain near the amino-terminus, could be phosphorylated by cAMP-dependent protein kinase unmasking a phosphorylation site which is not apparent in the native ABP protein.