A chromodomain (''
chromatin
organization
modifier''
) is a
protein structural domain of about 40–50
amino acid residues commonly found in proteins associated with the remodeling and manipulation of
chromatin. The domain is highly
conserved among both plants and animals, and is represented in a large number of different proteins in many
genomes, such as that of the
mouse
A mouse ( : mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus' ...
. Some chromodomain-containing
genes have multiple
alternative splicing
Alternative splicing, or alternative RNA splicing, or differential splicing, is an alternative splicing process during gene expression that allows a single gene to code for multiple proteins. In this process, particular exons of a gene may be ...
isoforms that omit the chromodomain entirely.
In
mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s, chromodomain-containing proteins are responsible for aspects of
gene regulation related to chromatin remodeling and formation of
heterochromatin
Heterochromatin is a tightly packed form of DNA or '' condensed DNA'', which comes in multiple varieties. These varieties lie on a continue between the two extremes of constitutive heterochromatin and facultative heterochromatin. Both play a role ...
regions.
Chromodomain-containing proteins also bind
methylated histones and appear in the
RNA-induced transcriptional silencing complex.
In histone modifications, chromodomains are very conserved. They function by identifying and binding to methylated
lysine
Lysine (symbol Lys or K) is an α-amino acid that is a precursor to many proteins. It contains an α-amino group (which is in the protonated form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −C ...
residues that exist on the surface of chromatin proteins and thereby regulate gene transcription.
See also
*
Bromodomain
A bromodomain is an approximately 110 amino acid protein domain that recognizes acetylated lysine residues, such as those on the ''N''-terminal tails of histones. Bromodomains, as the "readers" of lysine acetylation, are responsible in transducin ...
*
Chromo shadow domain
In molecular biology, the chromo shadow domain is a protein domain which is distantly related to the chromodomain. It is always found in association with a chromodomain. Proteins containing a chromo shadow domain include '' Drosophila'' and huma ...
References
External links
Chromatin Remodeling: Chromodomainsa
cellsignal.com
Protein domains
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