Chromosome regions enriched in hyperacetylated histone H4 are preferred sites for endonuclease- and radiation-induced breakpoints.
Previously, we have shown that breakpoints induced by the endonucleases AluI, BamHI and DNase I in CHO chromosomes are localized mainly in G-light bands. Neutrons and gamma rays produced similar breakpoint clusters to endonucleases in most CHO chromosomes. Here we compare endonuclease- and radiation-induced breakpoint maps with hyperacetylation patterns of histone H4. The H4 acetylation pattern in chromosomes is similar to the pattern of G-light, or R-bands, and breakpoints are clustered in highly acetylated chromosome regions. These findings indicate that chromosomal aberrations occur more frequently in active than in inactive chromatin.
Martínez-López
W
W
Faculty of Sciences, University of the Republic, Montevideo, Uruguay. wlopez@iibce.edu.uy
Folle
G A
GA
Obe
G
G
Jeppesen
P
P
D000107:Acetylation; D000818:Animals; D016466:CHO Cells; D002478:Cells, Cultured; D002843:Chromatin / Q000378:metabolism; D002871:Chromosome Banding; D002875:Chromosomes / Q000187:drug effects* / Q000528:radiation effects*; D006224:Cricetinae; D004249:DNA Damage; D004720:Endonucleases / Q000378:metabolism*; D006657:Histones / Q000235:genetics* / Q000378:metabolism; D007091:Image Processing, Computer-Assisted; D007621:Karyotyping; D014158:Transcription, Genetic
D002843:Chromatin; D006657:Histones; D004720:Endonucleases