HERC4 interacts with the c-Maf protein. (A) Affinity-purification assay was performed using an anti-HA–specific antibody. c-Maf, HERC4, and USP5 were indicated by the arrows. (B) The HERC4-unique peptides identified by MS/MS are highlighted in yellow. (C) HEK293 cells were transiently transfected with HA-c-Maf and or HERC4 for 48 hours. Cell lysates were subjected to IP with a HERC4 antibody and subsequent IB with c-Maf or HERC4 antibodies. (D) MM1.S cells were infected with HERC4 lentivirus. Ninety-six hours later, cell lysates were prepared for co-IP with a c-Maf–specific antibody, followed by IB with a HERC4-specific antibody. (E) NIH3T3 cells were transfected with c-Maf, HERC4, or both plasmids; 48 hours later, cells were subjected to immunofluorescent staining and confocal analysis.