Cleavage of actin by interleukin 1 beta-converting enzyme to reverse DNase I inhibition

Three of the predominant features of apoptosis are internucleosomal DNA fragmentation, plasma membrane bleb formation, and retraction of cell processes, We demonstrate that actin is a substrate for the proapoptotic cysteine protease interleukin 1 beta-converting enzyme. Actin cleaved by interleukin 1 beta-converting enzyme can neither inhibit DNase I nor polymerize to its filamentous form as effectively as intact actin, These findings suggest a mechanism for the coordination of the proteolytic, endonucleolytic, and morphogenetic aspects of apoptosis.