The retarded electrophoretic migration of p56lck induced by vanadate in lymphoma cells correlates with modified kinase activity

Abstract p56 lck is a src related lymphocyte specific tyrpsine protein kinase which undergoes specific changes during T-cell activation, particularly the appearance of slow migrating forms. To analyze these forms, LSTRA cells were treated with vanadate. This resulted in increased phosphorylation of p56 lck with the appearance of slow migrating forms. Renaturation of the p56 lck bands after gel migration showed that vandate mostly increased the activity of the lower band of p56 lck . The upper bands had a reduced specific activity. In addition, the upper bands from vanadate treated cells displayed additional phosphorylated sites.