Inactivation of Mre11 does not affect VSG gene duplication mediated by homologous recombination in Trypanosoma brucei.
J Biol Chem
; 277(29): 26185-93, 2002 Jul 19.
Article
em En
| MEDLINE
| ID: mdl-12011090
We demonstrate, by gene deletion analysis, that Mre11 has a critical role in maintaining genomic integrity in Trypanosoma brucei. mre11(-/-) null mutant strains exhibited retarded growth but no delay or disruption of cell cycle progression. They showed also a weak hyporecombination phenotype and the accumulation of gross chromosomal rearrangements, which did not involve sequence translocation, telomere loss, or formation of new telomeres. The trypanosome mre11(-/-) strains were hypersensitive to phleomycin, a mutagen causing DNA double strand breaks (DSBs) but, in contrast to mre11(-/-) null mutants in other organisms and T. brucei rad51(-/-) null mutants, displayed no hypersensitivity to methyl methanesulfonate, which causes point mutations and DSBs. Mre11 therefore is important for the repair of chromosomal damage and DSBs in trypanosomes, although in this organism the intersection of repair pathways appears to differ from that in other organisms. Mre11 inactivation appears not to affect VSG gene switching during antigenic variation of a laboratory strain, which is perhaps surprising given the importance of homologous recombination during this process.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Trypanosoma brucei brucei
/
Glicoproteínas Variantes de Superfície de Trypanosoma
/
Duplicação Gênica
/
Proteínas de Saccharomyces cerevisiae
/
Reparo do DNA
/
Endodesoxirribonucleases
/
Exodesoxirribonucleases
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2002
Tipo de documento:
Article