It has been shown that about 50 % of the
whole chromatin DNA exists in a very compact form in calfthymus
chromatin.These compact fragments can be extracted
from the whole chromatin as nuclease resistant fragments
by limited nuclease digestion. These fragments involve four
out of five histones in folding the...
During karyokinesis in the ciliate, Tetrahymena pyriformis, strain GL-I, an extranuclear chromatin body (ECB) is frequently formed as an excluded mass between the two dividing daughter macronuclei. The formation and fate of ECB's were followed by means of Feu lgen, toluidine blue 0, and euchrysine staining and autoradiography (³H-thymidine). The...
Chromatin DNA sequences intimately associated with the "core"
of the basic, repeating chromatin subunit are shown to be relatively
resistant to digestion by micrococcal nuclease. Chromatin DNA
sequences lying between adjacent chromatin subunits, as well as
DNA sequences in regions of chromatin which are free of chromatin
subunits, are subject...
In this work, the four yeast inner histones were prepared by the
use of consecutive slab gel fractionation. The use of this technique
allowed the first complete fractionation and rigorous identification of
the four yeast inner histones, and made possible a study of their
complexing behavior.
Variants and adjuncts of...
This work represents the first study of the conformational changes in histone H1 subfractions as well as the interactions of these subfractions with two nonhistone chromosomal (NHC) proteins. Calf thymus Hi was fractionated by the method of Kincade and Cole (1966a) using a very shallow guanidinium chloride gradient. A possible...
The nucleosome appears to be the basic structural unit of the
eukaryotic chromosome. The usual nucleosome preparation, isolated
from a micrococcal nuclease digest of nuclei, is heterogenous in DNA
length and protein composition with some particles containing spacer
DNA and associated protein. This heterogeneity complicated physical
and reconstitution studies. As...
The structure and transcriptional activity of intranuclear
and isolated chromatin from logarithmically growing
yeast cells has been compared to chromatin from cells which
have entered the stationary phase and ceased growing. Both
chromatins show a similar nucleosomal repeat pattern and a
160 by repeat size when digested with staphlococcal nuclease....
I examined, in three separate studies, the active chromatin
structure of the yeast, Saccharomyces cerevisiae.
Yeast contains four proteins having amino acid compositions
typical of the high mobility group (HMG) proteins. Three of these
are eluted from chromatin by 0.35 M NaCl; one is not, but is eluted
by 0.25...
Several levels of eukaryotic chromatin structure have
been observed: the nucleosome, the 10 nm and 30 nm fibers
and loop domains, apparently attached to the nuclear
matrix. In this research, the structure and function of
chromatin at two of these levels was investigated, with
studies on both nucleosome positioning and...