An additional transcript of the cdc25C gene from A431 cells encodes a functional protein

Citation
M. Bureik et al., An additional transcript of the cdc25C gene from A431 cells encodes a functional protein, INT J ONCOL, 17(6), 2000, pp. 1251-1258
Citations number
47
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Onconogenesis & Cancer Research
Journal title
INTERNATIONAL JOURNAL OF ONCOLOGY
ISSN journal
1019-6439 → ACNP
Volume
17
Issue
6
Year of publication
2000
Pages
1251 - 1258
Database
ISI
SICI code
1019-6439(200012)17:6<1251:AATOTC>2.0.ZU;2-I
Abstract
Human p53 protein was found to be functional in fission yeast in terms of g rowth repression and checkpoint control. Expression of wild-type p53 or the hut spot mutant p53(His273) results in dramatic motphological changes and loss of viability of recipient yeast cells. Overexpression of cdc25C phosph atase, the mitotic activator of cdc2, results in suppression of a p53-induc ed growth arrest. In order to understand the interplay between p53 and cdc2 5C in mammalian cells we isolated and sequenced cdc25C cDNA from the epider moid carcinoma cell line A431, which is known to carry the P53(His273) muta tion. Two different ent transcripts of the human cdc25C gene were detected by RT-PCR analysis - one full-length transcript and a shortened version (cd c25Cdm) that carries two deletions in the 5'-region of the gene. In normal human skin fibroblasts only one full-length cdc25C transcript was detected. The two different transcripts code fur proteins with a molecular weight of 55 kDa and 46 kDa, respectively. Both cdc25C cDNAs from A431 cells were fo und to complement A conditional lethal cdc25.22 mutant strain ain as well a s a cdc25 deletion strain of Schizosaccharomyces pombe indicating that func tional proteins were translated. Expression of cdc25Cdm variant leads to a stronger uncoupling of DNA replication from mitosis than expression of cdc2 5C suggesting that the deletion within the amino-terminus of cdc25C leads t o a protein which might contribute some potential fur oncogenic transformat ion, As with cdc25C, uncoupling of the DNA synthesis checkpoint by cdc25Cdm was reversed by coexpression of wild-type p53.