Mononucleosomes assembled on a DNA fragment containing (GGA/TCC)(n) repeats can form a DNA-DNA complex.
A DNA fragment of 163 bp containing 11 GGA repeats formed two-end positioned mononucleosomes as efficiently as that of CTG repeats. However, the rotational positioning of the GGA fragment was weak because clear DNase I cleavage patterns with 10-base periodicity were not seen near the center of the GGA fragment but were detected in the entire region of the CTG fragment. Incubation of the GGA mononucleosomes with the same fragment provided the DNA-DNA complex, which had been shown by using naked DNA fragments. DNase I digestion of the complex exhibited protection in the GGA repeats and in flanking sequences of about 30 bp at both sides, suggesting that both the repeat and flanking regions were involved in the association. Interestingly, histone H1, which enhanced DNA-DNA association on naked DNA, did not affect the complex formation on mononucleosomes. These results imply that GGA microsatellites in genomes could associate with one another at multiple sites and that the association may play a role in functional organization of higher order chromatin architecture.
Yoshimura
Akira
A
Division of Molecular Biology, Department of Gene Regulation, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan.
Ura
Kiyoe
K
Asakura
Hitoshi
H
Kominami
Ryo
R
Mishima
Yukio
Y
D002467:Cell Nucleus / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D002875:Chromosomes / Q000378:metabolism; D004247:DNA / Q000378:metabolism*; D053938:DNA Fragmentation; D003850:Deoxyribonuclease I / Q000378:metabolism; D006367:HeLa Cells; D006657:Histones / Q000378:metabolism; D006801:Humans; D008836:Micrococcal Nuclease / Q000378:metabolism; D018895:Microsatellite Repeats / Q000235:genetics; D008957:Models, Genetic; D009707:Nucleosomes / Q000378:metabolism*; D009841:Oligonucleotides / Q000378:metabolism; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D012091:Repetitive Sequences, Nucleic Acid; D013696:Temperature
D002843:Chromatin; D006657:Histones; D009707:Nucleosomes; D009841:Oligonucleotides; D004247:DNA; D003850:Deoxyribonuclease I; D008836:Micrococcal Nuclease