nucleosome


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nucleosome

 [noo´kle-o-sōm″]
any of the complexes of histone and DNA in eukaryotic cells, seen under the electron microscope as beadlike bodies on a string of DNA.

nu·cle·o·some

(nū'klē-ō-sōm'),
A localized aggregation of histone and DNA that is evident when chromatin is in the uncondensed stage.
Synonym(s): nu body
[nucleo- + G. sōma, body]

nucleosome

(no͞o′klē-ə-sōm′, nyo͞o′-)
n.
Any of the repeating subunits of chromatin found in eukaryotes, consisting of a DNA chain coiled around a core of histones.

nu′cle·o·som′al (-sō′məl) adj.

nucleosome

A nucleic acid and protein complex, which is the basic structural unit of chromatin, composed of a segment of DNA wrapped around a core of histone molecules.

nu·cle·o·some

(nū'klē-ō-sōm)
A localized aggregation of histone and DNA that is evident when chromatin is in the uncondensed stage.
[nucleo- + G. sōma, body]

nucleosome

The structural subunit of CHROMATIN consisting of about 200 BASE PAIRS and a barrel-shaped core of eight histone protein molecules (an octamer).

nucleosome

the basic structural unit of the eukaryote chromosome, being composed of four pairs of HISTONE proteins (H2A, H2B, H3 and H4) that are combined to form an octomer around which is wrapped about 150 nucleotide pairs of DNA.
References in periodicals archive ?
te Velthuis et al., "A plasma nucleosome releasing factor (NRF) with serine protease activity is instrumental in removal of nucleosomes from secondary necrotic cells," FEBS Letters, vol.
In addition, VolitionRx said it has discovered that cancer-related proteins that form bonds with chromosomes in living cancer cells can be detected and measured bound to nucleosomes circulating in the blood of cancer patients.
The first step in that direction is to make an initial nucleosome map to serve as a reference.
Several of the peaks can be interpreted in terms of the known biochemistry of the nucleosome, and owing to the genetic differences between donor and recipient, Lo's group is able to report that circulating cell-free DNA is primarily hematopoietic in origin.
Autoantibodies, such as ribonucleoprotein/Smith (RNP/Sm), Sjogren's syndrome-A (SS-A), Ro-52, Sjogren's syndrome-B, polymyositis-systemic sclerosis, centromere B, double-stranded DNA (dsDNA), nucleosomes, histones, ribosomal protein, and proliferating cell nuclear antigen, were assessed by immunoblot technique.
Histone acetylation and deacetylation play an important part in the nucleosome modifications process.
Except for the significance of ACPAs in the diagnosis for RA, NET components, such as cell-free DNA, cell-free nucleosome, NE protein, and MPO protein, are also increased in RA patients that could also be potential biomarkers for RA diagnosis.
X-rays and microscopy show that the primary level of chromatin organization involves 147 bases of DNA spooling around proteins to form particles approximately 11 nanometers (nm) in diameter called nucleosomes. These nucleosome "beads on a string" then are thought to fold into discrete fibers of increasing diameter (30, 120, 320 nm, etc.) until they form chromosomes.
These methods can be divided into two broad categories: those that assess nucleosome positioning as a proxy for active/inactive chromatin and those that more specifically examine various types of histone modifications commonly associated with either transcriptional activity or repression (such as H3K4me3 or H3K9me3, respectively) (Bock and Lengauer 2008; Tsompana and Buck 2014) (Table 4).
Salient features included the peak fragment size frequency at 166 bp, reminiscent of a chromatosomal structure (approximately 146 bp nucleosome + approximately 20 bp linker), and a 10-bp periodicity in the descending size range.
Briefly, the dCas9-epieffector complex could achieve methylation and demethylation at DNA level, rewriting histone marks by inducing methylation or acetylation at nucleosome level, and be optimized to improve the editing efficiency (Figures 1 and 2, Table 1).