| Comments |
"The production of very homogeneous and
tightly folded 30-nm chromatin fibers from long nucleosome
arrays with different nucleosome repeat lengths has permitted [researchers]
to obtain accurate measurements of fiber dimensions and hence nucleosome packing ratios. Importantly, unlike previous chromatin reconstitution experiments (35, 38, 44), [their] nucleosome
arrays contain a native-like complement of linker histone (11),
which is critical for obtaining correct folding and maximal
compaction (15, 32, 45). [Researchers] find that over the range of nucleosome repeat lengths analyzed, there are two discrete classes of
fiber structure, one 33 nm in diameter and with
˜11 nucleosomes per 11 nm, and the other
˜44 nm in diameter and with
˜15 nucleosomes per 11 nm. This finding resolves the controversy in the literature, showing that the fiber diameter does not
increase linearly with linker length." |