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Tightly coiled chromosomal material that stains deeply during interphase and is believed to be genetically inactive.


(Biology) the condensed part of a chromosome that stains strongly with basic dyes in nondividing cells and has little genetic activity. Compare euchromatin


(ˌhɛt ər əˈkroʊ mə tɪn)

the dense, highly stainable part of a chromosome.
References in periodicals archive ?
colombica, (Table 1) with heterochromatin in the interstitial region of 4 chromosomes added to the centromeric heterochromatic blocks on all the chromosomes (Murakami et al.
Izpisua Belmonte added that more extensive studies will be needed to fully understand the role of heterochromatin disorganization in aging, including how it interacts with other cellular processes implicated in aging, such as shortening of the end of chromosomes, known as telomeres.
Histone H4 acetylation distinguishes coding regions of the human genome from heterochromatin in a differentiation-dependent but transcription-independent manner.
The organization of spindle microtubules in mitotic cells of Luzula luzuloides investigated Madej (1998) and a LCS1 sequence in heterochromatin in L.
Both of these types of epigenetic modifications work together to remodel the chromatin and partition the genome into two different functional domains-transcriptionally active regions collectively known as euchromatin and transcriptionally inactive regions collectively called heterochromatin.
143-145) This finding is important since senescence markers, such as senescence-associated heterochromatin foci, senescence-associated [beta]-galactosidase, or the transcription factor known as deleted in esophageal cancer 1 (DEC1), may potentiallybe used to differentiate low-grade dysplasia from high-grade dysplasia or carcinoma.
For hundreds of years before this discovery, scientists were puzzled by why heterochromatin clustered at the edge of the nucleus and how it was relevant to normal cell function.
Furthermore, cytogenetic results indicated that in dark morph specimens heterochromatin is restricted to three autosomal pairs (25 and Table 2) and low DNA content (Table 3), suggesting their close relationship with our non-Andean chromosomal group.
C-banding analyses and the evolution of heterochromatin among arvicolid rodents.
The nuclei were round and many were indented, and they featured both prominent nucleoli and small amounts of peripherally located heterochromatin.
While some of the mutations appear to specifically affect heterochromatin formation, other mutations have been found to exhibit partial alleviation of basal repression at the GALl promoter, as well as temperature-sensitive growth.
For example, along the "arms" of certain alfalfa chromosomes scientists identified thick bands of DNA and protein material called heterochromatin.