FIG 4.

Mutagenic analysis of putative phosphorylation sites within LCS I. The indicated mutations were engineered into mSGR-Luc-JFH-1 (29), in vitro-transcribed RNA was electroporated into Huh7 cells, and luciferase activity measured at 4 and 72 hpe. A polymerase-inactive mutant, GND, was included as a negative control. (A) Luciferase activity at 72 hpe is shown (n = 3) normalized to activity at 4 h. *, P < 0.05, significant difference from the wild type. (B) Western blot analysis of cell lysates at 72 hpe probed with NS5A (9E10) or GAPDH antibodies. “SSSAAA” refers to the S228/229/230A triple mutant, and “SSSDDD” refers to the corresponding S228/229/230D mutant.