chromatin


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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 nucleosomes and the higher order chromatin structures must be modified to facilitate the accessibility of these factors to hormone response sequences.
Studying mutations to the ATF-2 gene in Drosophila (dATF-2), the researchers observed a disruption to the heterochromatin structure and reduced methylation of histone proteins, the main component of chromatin.
Sham operated control rats showed that nuclear chromatin was faintly stained and homogeneously dispersed throughout the whole nucleus whereas I/R rat's apoptotic nuclei were clearly stained with typical condensed nuclei; condensed chromatin marginally located at the nuclear membrane or nuclear fragments consisting of condensed masses of chromatin were observed.
The significance of chromatin structure studies is more stressed owing to the greater awareness to transmission of genetic diseases because of higher incidence of gene imprinting defects, increased cancer frequency and other congenital and non-congenital defects in children conceived through assisted reproduction techniques.
After culture, the spermatozoa were flash frozen and analyzed for the percent damaged chromatin using the DNA fragmentation index (DFI).
knowlesi have been delineated, we were unable to find the ring form with double chromatin dots (9).
Chromatin has entered into separate agreements with Cibus and NRC-PBI, though the two projects will mirror each other.
In plants with an abnormal Pickle gene, however, the plant can't make chromatin remodeling factor.
While it seems that most nuclei do not suffer irreversible changes during differentiation, researchers have found that chromatin inside the nucleus of an adult cell differs considerably from that inside an egg cell or an early embryo.
The outcome of these attempts was the introduction of several sperm function tests including zona-free hamster oocyte penetration assay, sperm zona pellucida binding assay, acrosome reaction, sperm migration assay, computer aided sperm analysis (CASA), hyaluronon binding assay (HBA), sperm chromatin integrity and maturity (1).
Several suspects are mutations in genes that encode chromatin regulators - cellular proteins that govern how DNA is packed into the nucleus of a cell and how it is accessed when genes are expressed.
Increasingly, researchers are recognizing that neutrophils-cells better known for their role in immune defense-play an active role in DVT formation by releasing platelet-catching nets made of chromatin, a tightly-wound mix of DNA and associated proteins.