FIG. 6.

IE2 mutagenesis study. (A) Three mutant IE2 proteins, IE2C230S, IE2SUMO and IE2delC, with mutations (IE2C230S and IE2SUMO) or a deletion (IE2delC) within the RING, SUMO, and coiled-coil domains, respectively, were expressed by recombinant baculoviruses. The Western blot shows that all three mutant proteins were produced at similar levels and expected sizes. KKSE, lys-lys-ser-glu. (B) IE2 mutant viruses were cotransduced with vAcL and tested by luciferase assays. vAcIE2SUMO showed CMV promoter activation levels similar to those of vAcIE2, while both vAcIE2C230S and vAcIE2delC lost their activity.