Macronucleus
A type of nucleus in ciliates, involved in non-reproductive cell functions
A macronucleus (formerly also meganucleus) is the larger type of nucleus in ciliates. Macronuclei are polyploid and undergo direct division without mitosis. It controls the non-reproductive cell functions, such as metabolism. During conjugation, the macronucleus disintegrates, and a new one is formed by karyogamy of the micronuclei.
Macronuclei contain hundreds to thousands of chromosomes, each present in many copies.[1][2] There is no mechanism to precisely partition this complex genome equally during nuclear division; thus, how the cell manages to maintain a balanced genome after generations of divisions is unknown.
See also
- Micronucleus
References
- ^ Mochizuki K (2010-07-15). "DNA rearrangements directed by non-coding RNAs in ciliates". Wiley Interdisciplinary Reviews: RNA. 1 (3): 376–87. doi:10.1002/wrna.34. PMC 3746294. PMID 21956937.
- ^ Pevsner J (August 2015). Bioinformatics and Functional Genomics. John Wiley & Sons. ISBN 978-1-118-58176-6.
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