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(cell and molecular biology)
The portion of the chromosomes that stains with low intensity, uncoils during interphase, and condenses during cell division.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(also active chromatin), the portion of the chromatin that retains the uncoiled form of elementary deoxyribonucleoprotein (DNP) threads in the interval between cell divisions (that is, in the interphase), as opposed to the portion of the chromatin known as heterochromatin, which retains the coiled form. Euchromatin also differs from heterochromatin in that it participates in the intensive synthesis of ribonucleic acid (RNA) and contains a larger quantity of nonhistone proteins. Euchromatin contains not only DNP but also ribonucleoprotein granules, which have a diameter of 200–500 angstroms and serve to complete the maturation of the RNA and its transfer into the cytoplasm. Euchromatin contains most of the structural genes of an organism (seeCHROMOSOME).

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
The balance between heterochromatin and euchromatin is very dynamic.
Amiel et al., "Loss-of-function mutations in Euchromatin histone methyl transferase 1 (EHMT1) cause the 9q34 subtelomeric deletion syndrome," American Journal of Human Genetics, vol.
The nuclei possess fine granulated euchromatin and heterochromatin with the latter adjacent to the nuclear envelope (Fig.
(2005) noted that normal Bs consist of a diminutive short arm, a centromere, a proximal heterochromatin block, a stretch of euchromatin, followed by four blocks of heterochromatin and the distal-most euchromatin.
For mosaic tetrasomy 18p, the variability and severity of clinical phenotype might be influenced by euchromatin content, the degree of mosaicism, etc.
Furthermore, More, Raza, and Vince (2012) found that the diluent diacetyl had the potential to replace thymine with guanine in euchromatin regions, resulting in the disruption of hydrogen and disulfide bonds in the tertiary structure of enzymes important for mitosis.
Traditionally, euchromatin is considered an area of the genome that is transcriptionally active, while heterochromatin is transcriptionally silent.
Histone methyltransferases g9a and glp form heteromeric complexes and are both crucial for methylation of euchromatin at h3-k9.
[75] reported the global reduction of heterochromatin marker H3K9Me2, increase of euchromatin marker H3K4Me3, and increase of the transcriptional marker H3K36Me3 during the EMT progress, which are mostly dependent upon lysine-specific deaminase-1 (Lsd1).
Cell nucleus was elliptic in the center with a single nucleolus and had normal euchromatin and scattered heterochromatin.
Historically, chromatin has been classified as either euchromatin or heterochromatin, according to its compaction state, even though there is a spectrum of chromatin states, suggesting it to be a highly flexible macromolecule.