| Autor: |
Kato, Mitsuo V., Sato, Hiromi, Anzai, Hiroko, Nagayoshi, Mariko, Ikawa, Yoji |
| Předmět: |
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| Zdroj: |
Leukemia (08876924); Apr97 Supplement 3, Vol. 11, p389-392, 4p |
| Abstrakt: |
A murine erythroleukemic cell line (1-2-3) which expresses only the temperature-sensitive mutant p53 gene (Ata-to-Val substitution at codon 135) was established. When these cells were cultured at 32°C, the growth rate was reduced significantly and DNA fragmentation, a typical character of apoptosis, was observed. In this process, p53 migrated from cytoplasm to nucleus and protein complexes binding to the p53-responsive element were detected in nuclear extracts of the cells cultured at 32°C by gel-shift assay and transactivation from the p53-responsive element was detected. The expression of the p21 (waf1/cip1/sdi1), cyclin G and gadd45 genes was increased (about 3 to 4 fold that at 37°C), when the cells were cultured at 32°C. However, the expression of the bax gene was increased slightly (about 1.5 fold that at 37°C) and no significant change was detected in expression of the mdm2 gene. No change in the amount of Fas antigen was observed by flow cytometric analysis. Transcripts of the bc1-2 and fasl gene were not detected in the cells both at 37°C and 32°C. These results suggest that up-regulation of the genes associated with the cell cycle and/or DNA replication, such as p21, cyclinG and gadd45 rather than bax, fas, fasl and bcl-2 may be important for induction of apoptosis of this erythroleukemic cell line by p53. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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