Incorporation of DUF/FACT into chromatin enhances the accessibility of nucleosomal DNA.
DNA unwinding factor (DUF) was discovered as an essential DNA replication factor in Xenopus egg extracts. DUF consists of an HMG protein and a homolog of Cdc68p/Spt16p, and has the capability of unwinding dsDNA. Here we have examined the interaction of DUF with chromatin. DUF was incorporated into chromatin assembled from sperm heads and from plasmid DNA in egg extracts. It was revealed that the chromatin assembled in egg extracts immunodepleted of DUF is less sensitive to micrococcal nuclease (NNase) digestion than that assembled in control extracts, indicating that chromatin containing DUF has more decompact structure than that without DUF. Also we found that DUF has a high affinity for core histones in vitro. We suggest that the function of DUF may be to make the chromatin structure accessible to replication factors.
Seo
Hidetaka
H
Department of Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Okuhara
Koji
K
Kurumizaka
Hitoshi
H
Yamada
Takatomi
T
Shibata
Takehiko
T
Ohta
Kunihiro
K
Akiyama
Tetsu
T
Murofushi
Hiromu
H
D000818:Animals; D002843:Chromatin / Q000378:metabolism*; D002850:Chromatography, Gel; D004247:DNA / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006609:High Mobility Group Proteins / Q000235:genetics / Q000378:metabolism*; D006657:Histones / Q000378:metabolism; D008297:Male; D008836:Micrococcal Nuclease / Q000494:pharmacology; D009707:Nucleosomes / Q000378:metabolism*; D010063:Ovum / Q000378:metabolism; D011485:Protein Binding; D013094:Spermatozoa / Q000378:metabolism; D013997:Time Factors; D014981:Xenopus; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*
D002843:Chromatin; C473989:DNA unwinding factor , Xenopus; D006609:High Mobility Group Proteins; D006657:Histones; D009707:Nucleosomes; D029867:Xenopus Proteins; D004247:DNA; D008836:Micrococcal Nuclease