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Cyclin K as a direct transcriptional target of the p53 tumor suppressor.

ABSTRACT: Cyclin K, a newly recognized member of the "transcription" cyclin family, may play a dual role by regulating CDK and transcription. Using cDNA microarray technology, we found that cyclin K mRNA was dramatically increased in U373MG, a glioblastoma cell line deficient in wild-type p53, in the presence of exogenous p53. An electrophoretic mobility-shift assay showed that a potential p53-binding site (p53BS) in intron 1 of the cyclin K gene could indeed bind to p53 protein. Moreover, a heterologous reporter assay revealed that the p53BS possessed p53-dependent transcriptional activity. Colony-formation assays indicated that overexpression of cyclin K suppressed growth of T98G, U373MG and SW480 cells. The results suggested that cyclin K may play a role in regulating the cell cycle or apoptosis after being targeted for transcription by p53.

SUBMITTER: Mori T

PROVIDER: S-EPMC1531701 | biostudies-literature | 2002 May-Jun

REPOSITORIES: biostudies-literature

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Cyclin K as a direct transcriptional target of the p53 tumor suppressor.

Mori Toshiki T Anazawa Yoshio Y Matsui Kuniko K Fukuda Seisuke S Nakamura Yusuke Y Arakawa Hirofumi H

Neoplasia (New York, N.Y.) 20020501 3

Cyclin K, a newly recognized member of the "transcription" cyclin family, may play a dual role by regulating CDK and transcription. Using cDNA microarray technology, we found that cyclin K mRNA was dramatically increased in U373MG, a glioblastoma cell line deficient in wild-type p53, in the presence of exogenous p53. An electrophoretic mobility-shift assay showed that a potential p53-binding site (p53BS) in intron 1 of the cyclin K gene could indeed bind to p53 protein. Moreover, a heterologous ...[more]

PMID: 11988847

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