INVESTIGADORES
ARBELETCHE Lidia Beatriz
artículos
Título:
Chromatin condensation and differential sensitivity of mammalian and insect cells to DNA strand breaks induced by bleomycin
Autor/es:
D LOPEZ-LARRAZA, J PADRÓN, N E RONCI, LA VIDAL RIO; VIDAL RIOJA, LIDIA BEATRIZ ARBELETCHE
Revista:
MUTATION RESEARCH
Editorial:
Elsevier
Referencias:
Año: 2006 vol. 600 p. 93 - 101
ISSN:
0921-8262
Resumen:
Abstract
Bleomycin (BLM) induces DNA damage in living cells. In this report we analyzed the role of chromatin compactness in the
differential response of mosquito (ATC-15) and mammalian (CHO) cells to DNA strand breaks induced by BLM. We used cells
unexposed and exposed to sodium butyrate (NaB), which induces chromatin decondensation. By nucleoid sedimentation assay and
digestions of nuclei with DNAse I, untreated mosquito cells (no BLM; no NaB) were shown to have more chromatin condensation
than untreated CHO cells. By alkaline unwinding ATC-15 cells treated with NaB showed more BLM-induced DNA strand breaks
than NaB-untreated CHO cells. The time-course of BLM-induced DNA damage to nuclear DNA was similar for NaB-untreated
mammalian and insect cells, but with mosquito cells showing lessDNAstrand breaks, both at physiological temperatures and at 4 ◦C.
However, when DNA repair was inhibited by low temperatures and chromatin was decondensed by NaB treatments, differences in
BLM-induced DNA damage between these cells lines were no longer observed. In both cell lines, NaB did not affect BLM action
on cell growth and viability. On the other hand, the low sensitivity of ATC-15 cells to BLM was reflected in their better growth
efficiency. These cells exhibited a satisfactory growth at BLM doses that produced a permanent arrest of growth in CHO cells. The
data suggest that mosquito cells might have linker DNAs shorter than those of mammalian cells, which would result in the observed
both greater chromatin condensation and greater resistance to DNA damage induced by BLM as compared to CHO cells.
© 2006 Elsevier B.V. All rights reserved.
However, when DNA repair was inhibited by low temperatures and chromatin was decondensed by NaB treatments, differences in
BLM-induced DNA damage between these cells lines were no longer observed. In both cell lines, NaB did not affect BLM action
on cell growth and viability. On the other hand, the low sensitivity of ATC-15 cells to BLM was reflected in their better growth
efficiency. These cells exhibited a satisfactory growth at BLM doses that produced a permanent arrest of growth in CHO cells. The
data suggest that mosquito cells might have linker DNAs shorter than those of mammalian cells, which would result in the observed
both greater chromatin condensation and greater resistance to DNA damage induced by BLM as compared to CHO cells.
© 2006 Elsevier B.V. All rights reserved.
However, when DNA repair was inhibited by low temperatures and chromatin was decondensed by NaB treatments, differences in
BLM-induced DNA damage between these cells lines were no longer observed. In both cell lines, NaB did not affect BLM action
on cell growth and viability. On the other hand, the low sensitivity of ATC-15 cells to BLM was reflected in their better growth
efficiency. These cells exhibited a satisfactory growth at BLM doses that produced a permanent arrest of growth in CHO cells. The
data suggest that mosquito cells might have linker DNAs shorter than those of mammalian cells, which would result in the observed
both greater chromatin condensation and greater resistance to DNA damage induced by BLM as compared to CHO cells.
© 2006 Elsevier B.V. All rights reserved.
◦C.
However, when DNA repair was inhibited by low temperatures and chromatin was decondensed by NaB treatments, differences in
BLM-induced DNA damage between these cells lines were no longer observed. In both cell lines, NaB did not affect BLM action
on cell growth and viability. On the other hand, the low sensitivity of ATC-15 cells to BLM was reflected in their better growth
efficiency. These cells exhibited a satisfactory growth at BLM doses that produced a permanent arrest of growth in CHO cells. The
data suggest that mosquito cells might have linker DNAs shorter than those of mammalian cells, which would result in the observed
both greater chromatin condensation and greater resistance to DNA damage induced by BLM as compared to CHO cells.
© 2006 Elsevier B.V. All rights reserved.
Keywords: Bleomycin; DNA damage; Chromatin condensation; Mammalian and insect cellsBleomycin; DNA damage; Chromatin condensation; Mammalian and insect cells