Identification of product-substrate pattern for erythrocyte membranes self-digestion using the original two-dimensional electrophoretic technique.

Ghost proteins immobilized in polyacrylamide gel after SDS-PAGE (first dimension) were degraded by endogenous membrane proteases. Fragments of the gels were submitted to SDS-PAGE (second dimension). Undigested proteins appeared on a diagonal, whereas products of proteolysis were evident below the substrates on electropherograms. The typical product patterns for spectrin, band 3, 4.1 and 4.2 proteins for human and bovine ghosts, are described.