Autor: |
Sukhodolets, V., Botina, S., Trenina, M., Ukhabotina, L. |
Zdroj: |
Russian Journal of Genetics; May2001, Vol. 37 Issue 5, p476-485, 10p |
Abstrakt: |
Heterozygous tandem duplications formed in conjugational matings in Escherichia coliprovides a convenient model system for studying the evolution of bacterial chromosome. Heterozygous duplications segregate various classes of haploid and diploid recombinants that appear as a result of unequal crossing over between sister chromosomes. In this work, an extended tandem duplication in the deooperon of E. colicarrying deoA deoB::Tn 5/ deoC deoD thr::Tn 9alleles was examined. Recombination between homologous DNA repeats in the duplication was studied in strains carrying different combinations of recBC, sbcBC, recB::Tn 10, recQ::Tn 3and recF::Tn 3mutations. The frequency of recombination between homologous DNA repeats was very high in all strains and did not decrease when the RecBCD and RecF recombinational pathways were simultaneously damaged in strains with the recB sbcBC recQ(or recF) genotype. It is assumed that unequal crossing over between direct DNA repeats in duplications may proceed through a particular pathway of “adaptive” recombination. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
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