Fig. 3.
N1 inhibits ST-induced apoptosis in VACV-infected cells. HeLa cells were mock-infected or infected with vN1, vΔN1 or vN1-rev at 2 p.f.u. per cell for 2 h followed by treatment with (black bars) or without (white bars) 1 μM ST for 2 h (panel a) or the indicated times (panel b), and were assayed for caspase activity (a), and caspase-3 (p17 fragment) and PARP (p89 fragment) cleavage (b). (c) HeLa cells were mock-infected or infected with vN1 or vΔN1 at 10 p.f.u. per cell for 6 h and mitochondrial (M), organelle (O) and cytosolic (C) fractions were isolated by subcellular fractionation. Fractions were analysed by immunoblotting for N1, cytochrome c, α-tubulin and Bcl-xL. Data are means±sd (**/##P<0.005, ***P<0.0005; Student's t-test, n=3). Blots are representative of three individual experiments.