Organization of telomeric nucleosomes: atomic force microscopy imaging and theoretical modeling.
Telomeric chromatin has peculiar features with respect to bulk chromatin, which are not fully clarified to date. Nucleosomal arrays, reconstituted on fragments of human telomeric DNA and on tandemly repeated tetramers of 5S rDNA, have been investigated at single-molecule level by atomic force microscopy and Monte Carlo simulations. A satisfactory correlation emerges between experimental and theoretical internucleosomal distance distributions. However, in the case of telomeric nucleosomal arrays containing two nucleosomes, we found significant differences. Our results show that sequence features of DNA are significant in the basic chromatin organization, but are not the only determinant.
Mechelli
Rosella
R
Dipartimento di Genetica e Biologia Molecolare, Università di Roma La Sapienza, Fondazione Istituto Pasteur-Fondazione Cenci Bolognetti, Piazzale A. Moro 5, I-00185 Rome, Italy.
Anselmi
Claudio
C
Cacchione
Stefano
S
De Santis
Pasquale
P
Savino
Maria
M
D000818:Animals; D002645:Chickens; D006657:Histones / Q000737:chemistry; D006801:Humans; D018625:Microscopy, Atomic Force; D008962:Models, Theoretical; D009707:Nucleosomes / Q000737:chemistry* / Q000235:genetics / Q000648:ultrastructure; D012341:RNA, Ribosomal, 5S / Q000737:chemistry / Q000235:genetics; D012016:Reference Values; D012091:Repetitive Sequences, Nucleic Acid; D012617:Sea Urchins / Q000235:genetics; D016008:Statistical Distributions; D016615:Telomere / Q000737:chemistry*
D006657:Histones; D009707:Nucleosomes; D012341:RNA, Ribosomal, 5S