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Cards In This Set
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Nucleosome the basic repeat element of chromatin is the
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Nucleosome
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Interconnected by sections of
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Linker DNA
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A far shorter arrangement than pure
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DNA in solution
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In addition to core histones
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There is the linker histone, H1
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Which contacts the exit/entry of the DNA strand
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On the nucleosome
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The nucleosome core particle together with histone H1 is known as
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Chromatosome
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Nucleosomes with about 20 to 60 base pairs of linker DNA can form under non-physiological conditions an
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Appx 10nm beads on a string fibre
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The nucleosome bind DNA non specifically as required by their function
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In general DNA packaging
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There are however large DNA sequence preferences that govern
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Nucleosome positioning
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This is due primarily to the varying physical properties
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Of different sequences
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For instance adenosine and thymine are more favourably compressed into
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Inner minor grooves
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This means nucleosomes can bind preferentially at
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One position appx every 10 base pairs (the helical repeat of DNA)
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Whereas the DNA is rotated to maximise the number of A and T bases
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That will lie in the inner minor groove
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Nucleosome structure nucleosome are basic unit of
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DNA packaging in eukaryotes
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Consisting of a segment of DNA wound around a
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Histone protein core
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