Dinokaryon
Appearance
A dinokaryon is a eukaryotic nucleus present in dinoflagellates in which the chromosomes are fibrillar in appearance (i.e. with unmasked DNA fibrils) and are more or less continuously condensed.
The nuclear envelope does not break down during mitosis, which is thus termed closed mitosis, or "dinomitosis".[1] The mitotic spindle is extranuclear.[2]
Histones are absent.[3] However, recent EST sequencing has revealed the presence of histones in one of the closest relative to dinoflagellates, Perkinsus marinus and an early-branching dinoflagellate, Hematodinium sp.[4] However, histone-like proteins of bacterial origins are found in the coding regions at periphery of the dinokaryon's chromosomes.[5]
References
[edit]- ^ Gavelis, Gregory S.; Herranz, Maria; Wakeman, Kevin C.; Ripken, Christina; Mitarai, Satoshi; Gile, Gillian H.; Keeling, Patrick J.; Leander, Brian S. (2019-01-29). "Dinoflagellate nucleus contains an extensive endomembrane network, the nuclear net". Scientific Reports. 9 (1): 839. Bibcode:2019NatSR...9..839G. doi:10.1038/s41598-018-37065-w. ISSN 2045-2322. PMC 6351617. PMID 30696854.
- ^ Gornik, SG; Hu, I; Lassadi, I; Waller, RF (8 August 2019). "The Biochemistry and Evolution of the Dinoflagellate Nucleus". Microorganisms. 7 (8): 245. doi:10.3390/microorganisms7080245. PMC 6723414. PMID 31398798.
- ^ FENSOME R.A., TAYLOR F.J.R., NORRIS G., SARJEANT W.A.S., WHARTON D.I. & WILLIAMS G.L. 1993. A classification of living and fossil dinoflagellates. American Museum of Natural History, Micropaleontology, Special Publication 7: 1-351.
- ^ Gornik, S.G., Ford, K.L., Mulhern, T.D., Bacic, A., McFadden, G.I., and Waller, R.F.(2012). Loss of nucleosomal DNA condensation coincides with appearance of a novel nuclear protein in dinoflagellates. Curr. Biol. 22, 2303–2312
- ^ Gavelis, Gregory S.; Herranz, Maria; Wakeman, Kevin C.; Ripken, Christina; Mitarai, Satoshi; Gile, Gillian H.; Keeling, Patrick J.; Leander, Brian S. (2019-01-29). "Dinoflagellate nucleus contains an extensive endomembrane network, the nuclear net". Scientific Reports. 9 (1): 839. Bibcode:2019NatSR...9..839G. doi:10.1038/s41598-018-37065-w. ISSN 2045-2322. PMC 6351617. PMID 30696854.