Danio rerio
From Wikipedia, the free encyclopedia
| iDanio rerio | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 |
||||||||||||||
| Scientific classification | ||||||||||||||
|
||||||||||||||
|
|
||||||||||||||
| Danio rerio (Hamilton-Buchanan, 1822) |
Danio rerio commonly known as the Zebrafish is a tropical fish belonging to the minnow family (Cyprinidae), commonly kept in aquaria and used for scientific research. Zebra Danios are of no economic importance in commercial fisheries as a food fish, but very commonly known and popular in the aquarium trade.
Contents |
[edit] Characteristics
The fish is named for its five uniformly, pigmented, horizontal blue stripes on the side of the body; all extending to the anal fin onto the end of caudal fin rays of its tail.
Originating from the Ganges region in Eastern India as well as in Pakistan, Bangladesh, Nepal and Myanmar, it grows to about 2 inches (6 cm) and lives for around 5 years. The zebra danio, in its native range, commonly inhabits streams, canals, ditches, ponds and also occurs in slow-moving to stagnant water bodies, particularly rice fields.
In the aquarium trade, there are long-finned and other color forms of this danio, including a "Leopard" and "Longfin" danio. Recently, transgenic zebrafish have become commercially available that express green fluorescent protein or red fluorescent protein.
[edit] Aquarium Care
They are hardy fish and considered good for beginner aquarists. This species has been called one of the "bread and butter" fishes because of its ease of keeping, continued popularity, their beauty and perhaps its favorable price and availability.
The males are torpedo shaped and have gold stripes between the blue stripes; females have a larger, whiteish belly and have silver stripes instead of gold. An egg-scatterer, danios produce around 300 to 500 eggs in a single spawning. They are considered one of the easiest aquarium fish to breed.
Other fish also share the name zebrafish.
Zebra Danio are susceptible to Oodinium, or Velvet disease; Microsporidia (pseudoloma neurophilia),and mycobacterium spp.
[edit] Model organism for development and genetics
Zebra Danios serve as a common and useful model organism for studies of vertebrate development and gene function because they reproduce very easily, passing from the egg to the larvae stage in less than three days. For genetic research groups, the zebrafish is an excellent test subject and is used in many labs to replace or to supplement higher vertebrate models, such as rats and mice. Danio rerio is one of the few species of fish to have been flown into space (See Animals in space). Aided by the transparency of the embryo, if researchers modify the fish's genotype at the egg stage they can see resulting changes in organ shape or dynamics barely three days later. The arrival of zebrafish as a major model for studying developmental biology coincided with a large scale mutagenesis screen (commonly referred to as the Tübingen/Boston screens). The scholarly journal Development devoted an issue to research using the fish in celebration of this landmark. [1] A common reverse genetics technique is to knock down gene expression or modify splicing in zebrafish using Morpholino antisense technology; the journal Genesis devoted an issue to research using Morpholino oligos[2], mostly in Danio rerio. A known problem with zebrafish is that the genome underwent a duplication after the divergence of ray-finned fishes and lobe-finned fishes, and it is not always easy to silence one of the two gene orthologs reliably.
In addition, zebrafish have the ability to regenerate fins, skin, the heart and the brain (in larval stages). Researchers frequently cut the dorsal and ventral tail fins and analyze their regrowth to test for mutations. This research is leading the scientific community in the understanding of healing/repair mechanisms in vertebrates.
The results of genetic engineering in these fishes have been used to produce the Glofish, an aquarium pet with fluorescent pigments. Other varieties include golden, sandy and long fin fish.
In December 2005, a study of the golden strain identified the gene responsible for the unusual pigmentation of this strain as SLC24A5, a solute carrier that appears to be required for melanin production, and confirmed its function with a Morpholino knockdown. The orthologous gene was then characterized in humans and a one base pair difference was found to segregate strongly between fair skinned Europeans and dark skinned Africans. [3] This important study featured on the cover of the academic journal Science and demonstrates the power of zebrafish as a model organism in the relatively new field of comparative genomics.
[edit] Zebra danios as an introduced species
Zebra danios have been introduced and become established in Japan and the United States. The fish has also been sighted in Colombia, presumably escaped from an aquarium fish rearing facility and into local waters.
[edit] Former names and synonyms
- Barilius rerio
- Cyprinus chapalio
- Brachydanio rerio
- Cyprinus rerio
- Danio lineatus
- Nuria rerio
- Perilampus striatus
[edit] See also
[edit] References
- Danio rerio (TSN 163699). Integrated Taxonomic Information System. Accessed on 12 November 2004.
- "Danio rerio". FishBase. Ed. Ranier Froese and Daniel Pauly. October 2004 version. N.p.: FishBase, 2004.
- Lambert, Derek J (1997). Freshwater Aquarium Fish. Edison, New Jersey: Chartwell Books, Page 19. ISBN 0-7858-0867-1.
- Sharpe, Shirlie. Zebra Danio. Your Guide to Freshwater Aquariums. Retrieved on December 15, 2004.
- Kocher, Thomas D et. al.. Zebrafish, Vol. 2, #3, 2005 Roundtable Discussion- "Fish Models for Studying Adaptive Evolution and Speciation,".
- Zebrafish information network
[edit] External links
- The Zebrafish Information Network
- The Zebrafish International Resource Center
- Danio rerio
- Danio rerio embryonic development images
| Major Model Organisms in Genetic Studies |
|---|
| Lambda phage | E. coli | Chlamydomonas | Tetrahymena | Budding yeast | Fission yeast | Neurospora | Maize | Arabidopsis | C. elegans | Drosophila | Zebrafish | Rat | Mouse |
