Fig. 1. Ect2 localizes to the central spindle and the cortex of mitotic cells. (A) HeLa S3 cells grown on coverslips were fixed with paraformaldehyde and permeabilized with Triton X-100. Cells were then stained with anti-Ect2 antibodies. Different cell-cycle phases and a control cell treated for 24 hours with a siRNA targeting Ect2 are shown. Bar, 10 µm. (B) HeLa S3 cells were treated with GL2 and Ect2 siRNAs for 24 and 48 hours. Subsequently, cell lysates were prepared and proteins were separated by SDS-PAGE and transferred onto nitrocellulose membranes. These were probed with anti-Ect2 antibodies (upper panel) and, as a loading control, with anti--tubulin antibodies (lower panel).