Figure 5.

SENP1 regulates GATA1 SUMOylation. (A) Increased SUMOylated GATA1 in E13.5 SENP1 KO fetal liver. WT and KO fetal livers were dissected in the presence of 1 mM N-ethylmaleimide (deSUMOylase inhibitor) and total homogenates were subjected to Western blotting with anti-GATA1. Tubulin was used as a control. The SUMOylated form of GATA1 was determined by immunoprecipitation with anti-SUMO followed by Western blotting with anti-GATA1. The ratios of SUMO-GATA1/GATA1 were quantified. Data are representative from three pairs of embryos. (B) SENP1 deSUMOylates GATA1. GATA1 WT or GATA1-K137R was cotransfected with SENP1 WT or SENP1 CA in 293T cells as indicated. GATA1 and SENP1 proteins were detected by Western blotting with anti-GATA1 and anti-Flag, respectively. GATA1 conjugated with SUMO is indicated. Experiments were repeated three times.