If you can imagine wrapping a thick string around a cylinder, that is a basic picture of an NCL, with DNA strands being the string and a histone octamer, or protein being the cylinder. As seen in the image to the right, the 'nucleosome' refers to this whole string and ball structure of a 146-147bp (base pair) DNA strand wrapped around the histone. This tiny structure (10nm) has a lesser negative charge than isolated DNA, due to the positive core, with an overall charge of -150. The nucleosomes can be thought of as the building blocks of chromosomes, as multiple nucleosomes can be wound together to form chromatin fibers, which be further arranged to form chromosomes. The reason we are interested in these nucleosomes is that due to the small, dense and complex structures, not much is known about the processes that compacts nucleosomes into chromatin fibers.
We'll let that information be absorbed and talk about experimentation tomorrow. Foreign factor gone.
The charge is -150 what?
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