A cytoskeleton-associated protein, TMAP/CKAP2, is involved in the proliferation of human foreskin fibroblasts.
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.
Jeon
Sang-Min
SM
Department of Molecular Cell Biology and Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea.
Choi
Bongkun
B
Hong
Kyung Uk
KU
Kim
Eunhee
E
Seong
Yeon-Sun
YS
Bae
Chang-Dae
CD
Park
Joobae
J
D049109:Cell Proliferation; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D016193:G1 Phase / Q000502:physiology; D005786:Gene Expression Regulation; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D010766:Phosphorylation
C114988:CKAP2 protein, human; D003598:Cytoskeletal Proteins; D008869:Microtubule-Associated Proteins