A Balance between Nuclear and Cytoplasmic Volumes Controls Spindle Length
Fig 1
Spindle length increases proportionally with cell volume.
(A) Left panel: Blastomeres of mouse 2-cell embryos were microinjected with cRNAs encoding Histone-H2B fused to mCherry and Tubulin fused to EGFP. The following cells were used for experiments: intact two cell embryos (Intact), cells with double volume obtained by fusion of two blastomeres (2 fused), and cells with triple volume obtained by fusion of three blastomeres (3 fused). Right panel shows representative movie frames from time lapse imaging of each cell type in interphase and in mitosis; chromosomes are in red, spindle is in green, scale bar represents 10 μm. (B) The length of the spindle in 2 fused cells (35.26 ± 5.52 μm, n = 14) was not significantly increased (p = 0.1236) in comparison to the length of the spindle in Intact cells (32.38 ± 5.63 μm, n = 28). (C) The length of the spindle in 3 fused cells (40.71 ± 3.57 μm, n = 14) was significantly increased (p < 0.0001) in comparison to the length of the spindle in Intact cells (34.68 ± 3.99 μm, n = 23).
