chromatin

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Related to Chromatin structure: nucleosome

chromatin

 [kro´mah-tin]
the substance of the chromosomes, composed of DNA and basic proteins (histones), the material in the nucleus that stains with basic dyes.
sex chromatin the persistent mass of the material of the inactivated X chromosome in cells of normal females; called also Barr body.

chro·ma·tin

(krō'ma-tin),
The genetic material of the nucleus consisting of deoxyribonucleoprotein that occurs in two forms during the phase between mitotic divisions: as heterochromatin, seen as condensed, readily stainable clumps; as euchromatin, dispersed lightly staining or nonstaining material. During mitotic division the chromatin condenses into chromosomes.
[G. chrōma, color]

chromatin

/chro·ma·tin/ (kro´mah-tin) the substance of chromosomes, the portion of the cell nucleus that stains with basic dyes. See euchromatin and heterochromatin.
sex chromatin  Barr body; the persistent mass of the inactivated X chromosome in cells of normal females.

chromatin

(krō′mə-tĭn)
n.
A complex of nucleic acids and proteins, primarily histones, in the cell nucleus that stains readily with basic dyes and condenses to form chromosomes during cell division.

chro′ma·tin′ic adj.

chromatin

[krō′mətin]
Etymology: Gk, chroma, color
the material within a cell nucleus from which the chromosomes are formed. It consists of fine, threadlike strands of DNA attached to proteins called histones and is readily stained with basic dyes. Chromatin occurs in two forms, euchromatin and heterochromatin, which are distinguishable during the phases of the cell cycle by their different degrees of staining, which in turn depends how tightly they are coiled. During cell division, portions of the chromatin condense and coil to form the chromosomes. Also called chromoplasm, karyotin. See also chromatid, euchromatin, heterochromatin, sex chromatin. chromatinic, adj.
enlarge picture
Rim of chromatin outlining the nuclear membrane

chromatin

The threadlike stainable material seen in nuclei during interphase, which corresponds to chromosomes (nucleic acids/DNA, associated histones, and other proteins bundled into nucleosomes) in the eukaryotic nucleus.

chromatin

Genetics The stainable material of interphase nuclei corresponding to chromosomes; chromatin consists of nucleic acids–DNA and associated histone protein, which are packed into nucleosomes; euchromatin is loosely packed and accessible to RNA polymerases. See Salt & pepper chromatin. Cf Heterochromatin.

chro·ma·tin

(krō'mă-tin)
The genetic material of the nucleus, consisting of deoxyribonucleoprotein. During mitotic division, the chromatin condenses into chromosomes.
[G. chrōma, color]

chromatin

DNA. The elongated, fine-stranded complex of roughly equal quantities of DNA and the protein histone, from which chromosomes are made by condensing into a coil. The individual chromosomes cannot be distinguished in a chromatin strand.

chromatin

that part of the cell nucleus which becomes deeply stained with basic dyes. This is now known to be chromosomal material consisting of DNA together with HISTONE and nonhistone proteins.

chromatin

nuclear genetic material, which condenses (during cell division) into chromosomes

chro·ma·tin

(krō'mă-tin)
The genetic ma terial of the nucleus, consisting of deoxy ribonucleoprotein. During mitotic division, the chromatin condenses into chromosomes.
[G. chrōma, color]

chromatin (krō´mətin),

n the genetic material present in the nucleus, consisting of DNA and associated proteins, seen as irregular clumps in quiescent cells.

chromatin

the substance of the chromosomes, composed of nucleic acids and basic proteins (histones), the material in the nucleus that stains with basic dyes.

sex chromatin
Barr body; the persistent mass of the material of the inactivated X chromosome in cells of normal females. See also drumstick.
References in periodicals archive ?
The state of sperm chromatin structure is not significantly correlated with boar semen sensitivity defined on the basis of the frequency of secondary morphological changes in spermatozoa (Table 4).
Sperm chromatin structure assay (SCSA): a tool in diagnosis and treatment of infertility.
Histone post-translational modifications play an important role in modulating dynamic changes in chromatin structure and gene expression.
Although the mechanisms by which alcohol impacts chromatin structure are not completely understood, recent work suggests that some epigenetic changes result from altered cellular metabolism.
The genome project has also detected a large amount of functional modifications related to the chromatin structure, and this has permitted defining two types ofregions in the genome: a) <<active>> domains, which would be the regions defined by high transcription levels, early replication, histone H3 acetylation, and demethylation of lysine 27 of histone H3 (H3K27) (16); b) <<inactive>> domains, corresponding to regions of latent replication with scant transcriptional activity, low H3 acetylation and methylation of H3K27.
Knowing how the sperm chromatin structure is affected would facilitate a more precise knowledge of the structure of this hybrid zone.
The first part provides a detailed mechanical view of the processes involved in gene expression, including chromatin structure, transcription, and post-transcriptional processes.
Flow cytometric evaluation of boar semen by the sperm chromatin structure assay as related to cryopreservation and fertility.
For these reasons understanding the sperm chromatin structure, etiology of sperm chromatin abnormality, identification factors that disturbs sperm chromatin integrity and the mechanism of their action can help in recognizing the causes of couples' infertility.
8] 8:40 ANALYSIS OF CHROMATIN STRUCTURE IN THE MYELOID-LYMPHOID LEUKEMIA GENE TRANSLOCATION BREAKPOINT CLUSTER REGION.
The heritable alterations in chromatin structure by acetylation of histone and non histone proteins or DNA methylation patterns alter the expression of tumour suppressor genes or oncogenes associated with particular types of cancer (3).
This process opens the chromatin structure, facilitating transcription by allowing promoter binding to transcription factors and coactivator proteins (5, 6).