V-1–null cells grow slowly and may have a partial defect in cytokinesis. (A) Representative growth curves for WT cells (WT), V-1–null cells (V-1 Null), V-1–null cells expressing FLAG-V-1 (V-1 Null + V-1), and V-1–null cells expressing FLAG-FBM V-1 (V-1 Null + FBM V-1) (see key). The values are means of duplicate samples. (B) Doubling times for the same groups of cells in A. Mean and SD values are as follows: WT, 12.7 ± 1.1; V-1–null, 21.6 ± 1.0; V-1–null + V-1, 14.7 ± 1.7; V-1–null + FBM V-1, 20.8 ± 1.0. (C) Cell densities at saturation for the same group of cells in A. Mean and SD values are as follows: WT, 10.8 ± 0.9; V-1–null, 6.2 ± 0.7; V-1–null + V-1, 9.1 ± 0.8; V-1–null + FBM V-1, 6.0 ± 0.8. Note that V-1–null cells were not quite fully rescued by the reexpression of FLAG-V-1. (D) The distributions of WT and V-1–null cells (see key) with one, two, or three and greater nuclei. *P < 0.05; ***P < 0.001.