Phosphorylation of vasodilator stimulated phosphoprotein is correlated with cell cycle progression in HeLa cells

Vasodilator stimulated phosphoprotein (VASP) is known as an actin-binding protein. The phosphorylation of VASP plays an important role in its function. In a previous study, serine 157 phosphorylated VASP (p-VASP S157) was shown to be co-localized with α-tubulin on the spindle of SGC-7901 cells. In the present study, we demonstrated that the level of p-VASP S157 increases and has a peak which coincides with serine 10 phosphorylated histone 3 (p-H3 S10) during mitotic progression in a human cervical cancer cell line (HeLa cells). Application of protein kinase A inhibitor H89, protein kinase G inhibitor KT5823 and protein kinase C inhibitor Go6983, or a combination of these inhibitors, caused a partial decrease in p-VASP S157 and a delay in G2/M progression. Depletion of p-VASP S157 by VASP siRNA resulted in an increase in binucleated cells and x4n cells, a further delay in G2/M progression and the inhibition of HeLa cell proliferation. These results suggest that p-VASP S157 may play an important role in the G2/M transition and the completion of cytokinesis in HeLa cells.