| Autor: |
H. Nicoloff, L. Stoilov, K. Gecheff |
| Rok vydání: |
1980 |
| Předmět: |
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| Zdroj: |
Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis. 70:193-201 |
| ISSN: |
0027-5107 |
| DOI: |
10.1016/0027-5107(80)90159-1 |
| Popis: |
We have studied the influence of caffeine on the frequencies and location of MNNG and MH-induced aberrations in a reconstructed barley karyotype. We found a mutagen-dependent mechanism of caffeine action that was affected by the nature of the clastogen applied. Both mutagens induced chromatid aberrations of the delayed type. Post-treatment with caffeine significantly increased the frequencies of aberrations induced by these agents; the effect was more clearly pronounced with MNNG. There was no delay in the appearance of aberrations induced by MNNG (as opposed to MH) after caffeine post-treatment, an observation that is difficult to explain with the well-known mechanism of caffeine inhibition of post-replication repair. After treatment of barley with MNNG or MH, some intrachromosomal regions were preferentially involved in induced aberrations. Combined action of either of the mutagens with caffeine in general revealed a rather random distribution pattern of induced aberrations. Nevertheless, certain chromosomal segments were more sensitive to caffeine potentiation. Because it has been suggested that caffeine potentiation of the frequency of chemically induced chromosomal aberrations is connected with an inhibition of post-replication repair of primary lesions, it seems likely that the effect of caffeine on aberration distribution is coupled with more or less pronounced differential effectivity of repair processes in individual chromosomal regions. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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