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(cell and molecular biology)
A specialized chromomere to which the spindle fibers are attached during mitosis. Also known as kinetochore; kinomere; primary constriction.



a part of a chromosome that plays a fundamental role in its movement during cell division (mitosis). In the metaphase stage of mitosis, the area of the centromere within the chromosome is less dense than the chromosome’s other areas and forms a primary constriction that divides the chromosome into two sections; the position of this constriction is a basis for the classification of chromosomes. The cytoplasmic filaments (microtubules) of the spindle of cell division are attached to the centromere by their ends.

Some organisms, such as members of the genus Luzula and the scorpion, have polycentromeric chromosomes with a diffuse centromere and with the spindle filaments attached to the chromosome along its entire length. With a light microscope a cluster of chromomeres may be seen near the centromere of a chromosome during metaphase. Examination of mammalian cells with an electron microscope reveals a three-layered structure near each of the two longitudinal chromosome filaments, or chromatids. This structure is a kinetochore plate, whose interaction with the spindle filaments results in the even distribution of chromosomes among the daughter cells during cell division. Chromosomal aberrations involving the chromomere hamper the distribution of chromosomal material during mitosis and meiosis and alter the organism’s karyotype. Chromosomes that lack a centromere cannot take part in mitosis.


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Centromeric paint and specific locus probes were used when needed to investigate MYCC and MYCN amplification and chromosome 9 centromere.
The artificial chromosome will consist of only two telomeres joined by a centromere, forming a blank "cassette" into which researchers can insert single human genes for study,
The presence of one or more chromosomes with early or asynchronic separation of the centromere may be characteristic of a species or may result from the action of environmental agents (11-14).
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Further subdivision of translocation types can be made according to the exchange of chromosomal material and are classified as: (i) reciprocal, when segments from two different chromosomes have been exchanged; or (ii) robertsonian, in five acrocentric chromosomes (13, 14, 15, 21 and 22), where long arms fuse to form a single chromosome with a single centromere.
The SDR gametes contain sister chromatids from the centromere to the
Both chromosomes have heterochromatin on the centromere of this homeologous chromosome pair, while duplication of a portion of the centromeric heterochromatin may have modified the chromosome morphology.
com)-- During mitosis, spindle fibers attach to the centromere via the kinetochore.
The chromosome enumeration probes hybridizing to the centromere of the relevant chromosomes (LPE007R, Alpha satellite 7 Red; LPE017R, Alpha satellite 17 Red; LPE0YcR, Alpha satellite Y Red) were labelled with spectrum red.
IHC scoring (0, 1 + ,2 + ,3 +)is based on the relative intensity of tumor cell membrane staining with the HER2 antibody, whereas FISH scoring is based on counting the signals corresponding to immobilized fluorescent HER2 and chromosome 17 centromere (CEP17) hybridization probes.
The centromere is the chromosomal domain that directs the formation of the kinetochore, a proteinaceous structure that interacts with the spindle microtubules to ensure proper chromosmal segregation.