Highly synchronous culture of fibroblasts from G2 block caused by staurosporine, a potent inhibitor of protein kinases

Exp Cell Res. 1991 Jan;192(1):122-7. doi: 10.1016/0014-4827(91)90166-r.


The effect of staurosporine, a potent microbial inhibitor of protein kinases, on the cell cycle of cultured fibroblast cells was investigated. A low concentration of staurosporine (1-10 ng/ml) blocked the cell cycle of rat 3Y1 fibroblasts at the early G1 phase within 2 h after serum stimulation. On the other hand, a higher concentration of the drug (100 ng/ml) caused the specific G2 block. Both of these blocks were reversible. After release from the G2 block, highly synchronous transition to M phase was observed and both nuclear and cell divisions were completed within 180 min. This reversible G2 block showed a clear contrast to those by the other G2 arresters, trichostatin A and leptomycin B, which formed proliferative tetraploid cells after release by entering the cells into a new S phase without passage through M phase. The presence of trichostatin A or leptomycin B did not interfere with this synchronous progression through G2/M phases, suggesting that the arrest point of staurosporine was present in late G2 phase following those of trichostatin A and leptomycin B.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids / pharmacology*
  • Animals
  • Cell Cycle / drug effects*
  • Cell Division / drug effects
  • Cells, Cultured
  • Fibroblasts / cytology
  • Fibroblasts / drug effects
  • G1 Phase / drug effects
  • G2 Phase / drug effects
  • Protein Kinase C / antagonists & inhibitors*
  • Rats
  • S Phase / drug effects
  • Staurosporine


  • Alkaloids
  • Protein Kinase C
  • Staurosporine