Vesicular stomatitis virus hinders metaphase progression and causes mitotic cell death through M protein. (A) Synchronized NRK cells were mock infected or infected for 4 h with VSV or VSV M(D) at MOI 10. Infection was carried out in late G2 phase, before mitotic entry. Cells were then followed by high-resolution time-lapse microscopy until the end of mitosis. (t=min). (B) Synchronized NRK cells were mock infected or infected with VSV or VSV M(D) in early G1 for 4 or 7 h at MOI 10, and cell death in G1 or mitosis (as in A) was quantified (n=60). (C) Mitotic cell death that occurred during metaphase (in B) was quantified. (D) NRK cells were microinjected after nuclear envelope breakdown with GST, GST–M or GST–M(D) proteins along with FITC-dextran, as an injection marker. Injected cells were followed by time-lapse microscopy. (E) Data obtained in (D) were analysed and the percentage of viable cells was plotted. (F) Data obtained in (D) were analysed and the percentage of cell death in metaphase was plotted. *P<0.001. FITC, fluorescein isothiocyanate; GST, glutathione-S-transferase; M, matrix; MOI, multiplicity of infection; NRK, normal rat kidney; VSV, vesicular stomatitis virus.