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文章
Biegeleisen, K. (2014) Histone Structure. Part II. A Model
Which Places DNA in the N-Terminal Region of the Octamer. Slides
142-171.
被如下文章引用:
- TITLE: A New Histone Structure Which Binds DNA at Its Eight Subunit N-Termini
- AUTHORS: Ken Biegeleisen
- KEYWORDS: Histone, Octamer, Nucleosome, Protamine, Helix
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JOURNAL NAME: Open Access Library Journal
DOI: 10.4236/oalib.1102386
Feb 29, 2016
- ABSTRACT: A new model for the nucleosome is presented. The histone octamer core is
unchanged, but the location of the DNA is different. Since the highest number,
and highest concentration of positively- charged amino acid residues is located
not in the “superhelical ramp” of the octamer core, but rather in the domain of
the eight histone subunit N-termini collectively, the DNA is therefore placed
there. The role models for the protein and DNA structures in the N-terminal
domain are taken from the comparable role models for protein and DNA in the
protamine-DNA complex in sperm cells. The histone subunit N-termini are each
modeled as beta-strands, with psi/phi values of approximately /﹣130.5°
respectively, which gives a straight chain. The DNA is modeled according to the
“straight ladder” model of Tai Te Wu. Each DNA phosphate group is bound to a
lysine or arginine residue of histone by a 3 A salt bridge. The new model lends
itself so readily to further models of higher-order chromatin structure that
the problem shifts entirely, from one of deducing any higher-order structure at
all, to one of distinguishing between several models which compete for our
attention.
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