A cytoskeleton-associated protein, TMAP/CKAP2, is involved in the proliferation of human foreskin fibroblasts

Biochem Biophys Res Commun. 2006 Sep 15;348(1):222-8. doi: 10.1016/j.bbrc.2006.07.046. Epub 2006 Jul 18.


Previously, we reported the cloning of a cytoskeleton-associated protein, TMAP/CKAP2, which was up-regulated in primary human gastric cancers. Although TMAP/CKAP2 has been found to be expressed in most cancer cell lines examined, the function of CKAP2 is not known. In this study, we found that TMAP/CKAP2 was not expressed in G0/G1 arrested HFFs, but that it was expressed in actively dividing cells. After initiating the cell cycle, TMAP/CKAP2 levels remained low throughout most of the G1 phase, but gradually increased between late G1 and G2/M. Knockdown of TMAP/CKAP2 reduced pRB phosphorylation and increased p27 expression, and consequently reduced HFF proliferation, whereas constitutive TMAP/CKAP2 expression increased pRB phosphorylation and enhanced proliferation. Our results show that this novel cytoskeleton-associated protein is expressed cell cycle dependently and that it is involved in cell proliferation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Proliferation*
  • Cytoskeletal Proteins / metabolism*
  • Fibroblasts / cytology
  • Fibroblasts / metabolism*
  • G1 Phase / physiology
  • Gene Expression Regulation
  • Humans
  • Microtubule-Associated Proteins / metabolism
  • Phosphorylation


  • CKAP2 protein, human
  • Cytoskeletal Proteins
  • Microtubule-Associated Proteins