Figure 5

Interaction between SRSF1 and PRMT1. (A) Knock-down of SRSF1 or PRMT1 could reciprocally down-regulate each other. Both sh-SRSF1-1 and sh-SRSF1-2 are shRNA plasmids specific for SRSF1. sh-PRMT1 is the shRNA plasmid specific for PRMT1. sh-luc is the shRNA plasmid specific for firefly luciferase. sh-luc and untreated Nalm-6 cells were used as negative controls. (B) The expression of SRSF1 and PRMT1 were semi-quantified by Gel-pro analyzer software based on the western blot. The alterations of their expression levels were statistically analyzed. The knock-down of SRSF1 by sh-SRSF1-1 and sh-SRSF1-2 resulted in 1.90-fold (p = 0.022) and 1.73-fold (p = 0.028) decreases in the expression of PRMT1, respectively. The knock-down of PRMT1 by sh-PRMT1 resulted in a 1.86-fold decrease in the expression of SRSF1 (p = 0.000). (C) A co-immuno-precipitation assay was performed in Nalm-6 cells, and the results indicated that endogenous SRSF1 and PRMT1 can associate with each other in vivo. An IgG antibody was used as a negative control.