In vitro assembly of the CENP-B/alpha-satellite DNA/core histone complex: CENP-B causes nucleosome positioning.
BACKGROUND
We have studied the nucleosome structure formed from alpha-satellite DNA bound with CENP-B and core histones, in order to develop a previous proposal that the CENP-B dimer may play a critical role in the assembly of higher order structures of the human centromere by juxtaposing CENP-B boxes in long alpha-satellite arrays.


RESULTS
The dimeric structure of CENP-B was sufficiently stable to bundle together two 3.5 kbp DNA fragments when each DNA contained a CENP-B box. When the same length of DNA included two CENP-B boxes, the intra-molecular interaction with the CENP-B dimer predominated, resulting in the formation of loop structures. The in vitro assembly of CENP-B/alpha-satellite DNA/core histone complexes with the aid of nucleosome assembly protein-1 (NAP-1) permitted an investigation into the nucleosome arrangement in alpha-satellite DNA with CENP-B bound to CENP-B boxes. Footprint analyses with micrococcal nuclease (MNase) revealed that CENP-B causes nucleosome positioning between pairs of CENP-B boxes with unique hypersensitive sites created on both sides.


CONCLUSIONS
We propose that CENP-B functions as a structural factor in the centromere region in order to establish a unique, centromere specific pattern of nucleosome positioning.
Yoda
K
K
Bioscience Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-01, Japan.
Ando
S
S
Okuda
A
A
Kikuchi
A
A
Okazaki
T
T
D001324:Autoantigens; D001483:Base Sequence; D001665:Binding Sites; D018797:Cell Cycle Proteins; D002503:Centromere / Q000378:metabolism* / Q000648:ultrastructure; D051936:Centromere Protein B; D002843:Chromatin / Q000378:metabolism / Q000648:ultrastructure; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D004247:DNA / Q000648:ultrastructure; D018983:DNA Footprinting; D004276:DNA, Satellite / Q000378:metabolism*; D004268:DNA-Binding Proteins; D019281:Dimerization; D006657:Histones / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009687:Nuclear Proteins; D009690:Nucleic Acid Conformation; D056490:Nucleosome Assembly Protein 1; D009707:Nucleosomes / Q000378:metabolism*; D011485:Protein Binding; D011506:Proteins / Q000378:metabolism
D001324:Autoantigens; C497926:CENPB protein, human; D018797:Cell Cycle Proteins; D051936:Centromere Protein B; D002843:Chromatin; D002868:Chromosomal Proteins, Non-Histone; D004276:DNA, Satellite; D004268:DNA-Binding Proteins; D006657:Histones; C533557:NAP1L1 protein, human; D009687:Nuclear Proteins; D056490:Nucleosome Assembly Protein 1; D009707:Nucleosomes; D011506:Proteins; D004247:DNA