CELF1 and hepatocellular carcinoma: Recently, over-expression and knockdown studies with hepatoma and embryonic kidney cells demonstrated that SRSF3 and SRSF1 (previously known as SRp20 and SF2/ASF, respectively) bind to the exonic splicing enhancers in exon 11, increasing exon inclusion, but that CUG-binding protein CUG-BP1 (CELF1) causes exon skipping by binding an exonic silencer.