heterochromatinhighly condensed
chromatin that stains deeply; thought to be genetically inert
Source: Jenkins, John B. 1990.
Human Genetics, 2nd Edition. New York: Harper & Row ...
Full article >>>Heterochromatin is believed to serve several functions, from
gene regulation to the protection of the integrity of
chromosomes; all of these roles can be attributed to the dense packing of
DNA, ...
Full article >>>Heterochromatin that surrounds the
centromere. Specific regions of
heterochromatin always present and in both homologs of a
chromosome. See
satellite DNA.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z ...
Full article >>>The
heterochromatin common to all active
cells is designated constituitive
heterochromatin. It does not contain "genes".
Heterochromatin is not being
transcribed and consists, in part, of
satellite DNA.
Full article >>>Heterochromatin properties are mediated by
proteins specifically associated with sat
DNAs that, however, are poorly
characterized.
Full article >>>HeterochromatinThe term proposed by Heitz (1928) for parts of
chromosomes with an abnormal degree of contr
action or of staining properties at nuclear
divisions (Gk. heteros, different). Composed of
repetitive DNA, stains dark bands in
G-banding. (Cf.
Full article >>>Heterochromatin stains more strongly and is a more condensed
chromatin.
Euchromatin stains weakly and is more open (less condensed).
Euchromatin remains dispersed (uncondensed) during
Interphase, when
RNA transcription occurs.
Full article >>>Heterochromatin and
EuchromatinHeterochromatin is tightly wound
DNA and visible during
interphase. It is inactive because
DNA cannot be
transcribed while it is tightly wound.
Euchromatin is not tightly wound. It is active.
Full article >>>Heterochromatinis found in parts of the
chromosome where there are few or no genes, such as
centromeres and
telomeres ...
Full article >>>heterochromatin Chromatin that stains intensely and appears to represent inactive genetic areas.
heterochrony
Evolutionary change in the relative time of appearance or rate of development of
characteristics from ancestor to descendant.
Full article >>>Heterochromatin. Dark-stained regions of
chromosomes thought to be for the most part genetically inactive.
Heteroduplex. A double-
stranded
DNA molecule or
DNA-
RNA hybrid, where each
strand is of a different
origin.
Full article >>>Heterochromatin: Compact,
gene-poor regions of a
genome, which are enriched in
simple sequence repeats. As it can be impossible to
clone,
heterochromatin is often ignored when calculating the percentage of a
genome that has been
sequenced.
Full article >>>HeterochromatinChromatin is the extended form of
DNA-
protein complex present in the
nucleus during
interphase in eukaryotic
cells. It can be made visible by staining (thus the name which literaly means coloured material).
Full article >>>Heterochromatin. Dark-stained regions of
chromosomes thought to be for the most part genetically inactive.
Heteroduplex. A double-
stranded
DNA molecule or
DNA-
RNA hybrid, where each
strand is of a different
origin.
Heterogeneous nuclear RNA (
hnRNA).
Full article >>>hept- seven hetero- different
heterochromatin Chromatin which in a condensed, less accessible state and are thus frequently
transcriptionally silent. However, some
DNA is constitutive
heterochromatin (e.g.
Full article >>>It exists in two forms: less dense
euchromatin can be
transcribed, and
heterochromatin is highly condensed and cannot be
transcribed. Inactive X
chromosome of female
mammals is an example of
heterochromatin. See
Gene Expression.
Full article >>>'"/>