Two splice variants are derived from the caspase-9 gene, proapoptotic caspase-9a and
antiapoptotic caspase-9b, by either the inclusion or exclusion of an exon 3, 4, 5, and 6
cassette. Previous studies from our laboratory have shown that the alternative splicing of
caspase-9 and the phosphorylation status of SR proteins, a conserved family of splicing
factors, are regulated by chemotherapy and ceramide via the action of protein phosphatase-
1. In this study, a link between ceramide, SR proteins, and the alternative splicing of caspase …