(A) Schematic diagram of experimental micropipette setup for chromosome micromanipulation. One of the two pipettes (force pipette) has a long taper with a spring constant of 30–200 pN/μm, which is used to measure forces in the range of 10–1000 pN by monitoring its bending. A third pipette is used as the spray pipette to spray reagents directly onto an isolated chromosome. Lower right insert shows a mitotic chromosome from human HeLa cells, and the lower left insert shows its linear, reversible elasticity. (B-C) Depletion of SMC2 (hCAP-E) using siRNA in HeLa cells. Protein knockdown is verified by western blot (B), and (C) immunofluorescence staining of SMC2 in fixed cells 36 hrs after siRNA treatment, using anti-SMC2 antibody in both cases. Bar = 5 μm.