Schlafen 12 induces CDX2 transcription factor and its effects are blocked by reducing USP14 and UCHL5 deubiquitylase. (a,b) Caco-2 cells were transduced with Ad-CMV or Ad-SLFN12 for 72 hours and CDX2 or CDX4 protein was measured (n=5 for each, p>0.05). (c) Caco-2 cells were transduced with Ad-CMV or Ad-SLFN12 for 72 hours and CDX2 mRNA was assessed (n=5, p>0.05). (d) Caco-2 cells transfected with non-targeting siRNA5 (siNT5) or a combination of both USP14 (siUSP14) and UCHL5 (siUCHL5) siRNA followed by transduction with Ad-CMV or Ad-SLFN12 for 72 hours, lysis, and western blotting using CDX2 or GAPDH antibodies (n=6,*p<0.05). (e) ≈50% reduction of CDX2 by siRNA (siCDX2), data not shown prevents the induction of sucrase-isomaltase promoter activity by cotransfection with a SLFN12 plasmid (SI-P+SLFN12) in comparison to sucrase-isomaltase promoter activity after cotransfection with an empty vector control plasmid (P). In contrast, SI-P+SLFN12 induces sucrase-isomaltase promoter activity after transfection with non-targeting siRNA (siNT5). (n=6, *p<0.05). All statistics are by two-sided t test with Bonferroni corrections for multiple comparisons.