Role of homologous recombination in the alpha-particle-induced bystander effect for sister chromatid exchanges and chromosomal aberrations.
Radiat Res
; 164(2): 141-7, 2005 Aug.
Article
em En
| MEDLINE
| ID: mdl-16038585
ABSTRACT
The bystander effect for sister chromatid exchanges (SCEs) and chromosomal aberrations was examined in hamster cell lines deficient in either DNA-PKcs (V3 cells, deficient in nonhomologous end joining, NHEJ) or RAD51C (irs3 cells, deficient in homologous recombination, HR). Cells synchronized in G0/G1 phase were irradiated with very low fluences of alpha particles such that < 1% of the nuclei were traversed by an alpha particle. Wild-type cells showed a prominent bystander response for SCE induction; an even greater effect was observed in V3 cells. On the other hand, no significant induction of SCE was observed in the irs3 RAD51C-deficient bystander cells irradiated at various stages in the cell cycle. Whereas a marked bystander effect for chromosomal aberrations occurred in V3 cells, the induction of chromosomal aberrations in irs3 bystander cells was minimal and similar to that of wild-type cells. Based on these findings, we hypothesize that HR is essential for the induction of SCE in bystander cells; however, HR is unable to repair the DNA damage induced in NHEJ-deficient bystander cells that leads to either SCE or chromosomal aberrations.
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Base de dados:
MEDLINE
Assunto principal:
Recombinação Genética
/
Troca de Cromátide Irmã
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Aberrações Cromossômicas
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Efeito Espectador
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Partículas alfa
Limite:
Animals
Idioma:
En
Revista:
Radiat Res
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Estados Unidos