Figure 1.
Interphase cells (I) were categorized based on the number of their centrosomes (green) as detected with an anti-γ-tubulin antibody. DNA was counterstained with DAPI (red) and the cells visualized by differential interference contrast (DIC) microscopy. Type 1I (A) have 1–2 centrosomes. Type 2I (B) are mono-nucleated cells with multiple centrosomes while Type 3I (C) contain multiple centrosomes in a multi-nucleated cell. Mitotic cells (M) were categorized in a similar manner based on the number and orientation of their centrosomes with respect to the mitotic plate. Type 1M (D) have a bi-polar spindle with 1 centrosome on either side of the mitotic plate. Type 2M (E) mitoses are bi-polar but demonstrate coalescence of multiple centrosomes at either pole. Type 3M (F) are multipolar mitoses in which the chromosomes are pulled in more than two directions.