View source for Dikaryon

{{Short description|Nuclear feature unique to certain fungi}}
The '''dikaryon(karyogamy)''' is a [[cell nucleus|nuclear]] feature that is unique to certain [[fungi]]. (The green alga ''[[Derbesia]]'' had been long considered an exception,<ref>van den Hoek, C., D.G. Mann, and H.M. Jahns 1995. Algae: an introduction to phycology, p. 430. Cambridge University Press (623 pp).</ref> until the [[heterokaryotic]] hypothesis was challenged by later studies.<ref>{{cite journal |author=Lee, S. H. |author2=T. A. Motomura |author3=T. Ichimura |title=Karyogamy follows plasmogamy in the life cycle of ''Derbesia tenuissima'' (Chlorophyta) |journal=Phycologia |year=1998 |volume=37 |issue=5 |pages=330–333| doi=10.2216/i0031-8884-37-5-330.1}}</ref>) Compatible cell-types can fuse cytoplasms ([[plasmogamy]]). When this occurs, the two nuclei of two [[cell (biology)|cells]] pair off and cohabit without fusing ([[karyogamy]]). This can be maintained for all the cells of the [[hyphae]] by [[Synchronization|synchronously]] dividing so that pairs are passed to newer cells. In the [[Ascomycota]] this attribute is most often found in the [[Ascomycota#Formation of sexual spores|ascogenous hyphae and ascocarp]] while the bulk of the mycelium remains monokaryotic. In the [[Basidiomycota]] this is the dominant phase, with most Basidiomycota [[monokaryon]]s weakly growing and short-lived.
[[File:Fungus cell cycle-en.svg|thumb|Dikaryons shown in a Basidiomycete mitosis cycle]]
The formation of a dikaryon is a [[plesiomorphy|plesiomorphic]] character for the subkingdom [[Dikarya]], which consists of the [[Basidiomycota]] and the [[Ascomycota]]. The formation of [[crozier (mycology)|croziers]] in the Ascomycota and of [[clamp connection]]s in the Basidiomycota facilitates maintenance of the dikaryons. However, some fungi in each of these [[phylum|phyla]] have evolved other methods for maintaining the dikaryons, and therefore neither croziers nor clamp connections are ubiquitous in either phylum.
==Etymology==
The name ''dikaryon'' comes from the [[Greek language|Greek]] ''δι- (di-)'' meaning "two" and ''κάρυον (karyon)'' meaning "[[Nut (fruit)|nut]]", referring to the [[cell nucleus]].
==See also==
{{Portal|Fungi}}
*[[Binucleated cells]] (as a pathological state)
*[[Heterokaryon]]
*[[Multinucleated cells]]
*[[Syncytium]]
==References==
{{Reflist}}
==External links==
*[https://web.archive.org/web/20120206053012/http://www.fungionline.org.uk/7sexual/5dikaryon.html Fungi Online Page, Formation of Dikaryons]
*[http://website.nbm-mnb.ca/mycologywebpages/NaturalHistoryOfFungi/DikaryaDiscussion.html]
[[Category:Mycology]]
{{Mycology-stub}}