mHerC6 is essential for global cellular ISG15 conjugation in mouse cells.

<p>(A) mRNA knock-down of HerC6 was analyzed by RT-qPCR in mouse L929 cells transfected with siRNAs specifically targeting human or mouse HerC6 and subsequently treated with recombinant type I IFN. mRNA levels in mHerC6 knock-down cells are plotted relative to mRNA levels in cells with non-targeting hHerC6 siRNA. Experiments were reproduced at least twice; a representative experiment is shown. Error bars represent standard deviation of qPCR replicates. B/C. L-929 cells were transfected with (B) indicated siRNAs, stimulated with IFN for 48 h and probed for endogenous ISG15 on a Western blot or (C) simultaneously transfected with a V5-tagged mouse ISG15 plasmid and indicated siRNAs, stimulated with IFN for 48 h and subsequently analyzed for global ISG15 conjugation by V5-specific immunoblot.