Nurturing Life Sciences
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Oligonucleotide-directed mutagenesis
The basic PCR mutagenesis system involves the use of two primary PCR reactions to produce two overlapping DNA fragments, both bearing the same mutation in the overlap region; this technique is thus termed overlap extension PCR .
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#Unit 2. Cellular Organization
Individual nucleosomes can be obtained by treating chromatin with the endonuclease micrococcal nuclease (MNase), which cuts the DNA between nucleosomes, a region known as linker DNA.
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Mononucleosomes typically have 200 bp DNA. End-trimming reduces the length of DNA first to 165 bp and then generates core particles with 146 bp.
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Mnase digestion result on centrifugation and electrophoresis
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Core DNA has an invariant length of 146 bp the minimum length of DNA needed to form a stable monomeric nucleosome, and is relatively resistant to digestion by nucleases.
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Core DNA invariant length of 146 bp contains core and linker histones so Mnase cuts after H1 binding site.
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The nucleosome is a disc with DNA organized into 12/3 turns around the surface.