- Chromomere
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A chromomere, also known as an idiomere, is one of the serially aligned beads or granules of an eukaryotic chromosome, resulting from local coiling of a continuous DNA thread.[1] It is visible on a chromosome during the prophase of meiosis and mitosis. Giant banded (Polytene) chromosomes resulting from the replication of the chromosomes and the synapsis of homologs without cell division is a process called endomitosis. These chromosomes consist of more than 1000 copies of the same chromatid that are aligned and produce alternating dark and light bands when stained. The dark bands are the chromomere.
The chromomeres are present during leptotene phase of prophase I during meiosis. During zygotene phase of prophase I, the chromomeres of homologs align with each other to form homologous rough pairing (homology searching). These chromomeres helps provide a unique identity for each homologous pairs.
There are more than 2000 chromomeres on 20 chromosomes of maize.
References
External links
- "Preparation and analysis of spermatocyte meiotic pachytene bivalents of pigs for gene mapping" - Nature
- "Physical mapping of DNA repetitive sequences to mitotic and meiotic chromosomes of Brassica oleracea var. alboglabra by fluorescence in situ hybridization" - Nature
- "Chromonema and chromomere" - Springerlink
Categories:- Chromosomes
- Genetics stubs
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