title: Vertebrate genome evolution and the zebrafish gene map.
abstract: In chordate phylogeny, changes in the nervous system, jaws, and appendages transformed meek filter feeders into fearsome predators. Gene duplication is thought to promote such innovation. Vertebrate ancestors probably had single copies of genes now found in multiple copies in vertebrates and gene maps suggest that this occurred by polyploidization. It has been suggested that one genome duplication event occurred before, and one after the divergence of ray-finned and lobe-finned fishes. Holland et al., however, have argued that because various vertebrates have several HOX clusters, two rounds of duplication occurred before the origin of jawed fishes. Such gene-number data, however, do not distinguish between tandem duplications and polyploidization events, nor whether independent duplications occurred in different lineages. To investigate these matters, we mapped 144 zebrafish genes and compared the resulting map with mammalian maps. Comparison revealed large conserved chromosome segments. Because duplicated chromosome segments in zebrafish often correspond with specific chromosome segments in mammals, it is likely that two polyploidization events occurred prior to the divergence of fish and mammal lineages. This zebrafish gene map will facilitate molecular identification of mutated zebrafish genes, which can suggest functions for human genes known only by sequence.
authors.affiliation: Institute of Neuroscience, University of Oregon, Eugene 97403-1254, USA. jpostle@oregon.uoregon.edu
authors.forename: J H
authors.initials: JH
authors.lastname: Postlethwait
authors.forename: Y L
authors.initials: YL
authors.lastname: Yan
authors.forename: M A
authors.initials: MA
authors.lastname: Gates
authors.forename: S
authors.initials: S
authors.lastname: Horne
authors.forename: A
authors.initials: A
authors.lastname: Amores
authors.forename: A
authors.initials: A
authors.lastname: Brownlie
authors.forename: A
authors.initials: A
authors.lastname: Donovan
authors.forename: E S
authors.initials: ES
authors.lastname: Egan
authors.forename: A
authors.initials: A
authors.lastname: Force
authors.forename: Z
authors.initials: Z
authors.lastname: Gong
authors.forename: C
authors.initials: C
authors.lastname: Goutel
authors.forename: A
authors.initials: A
authors.lastname: Fritz
authors.forename: R
authors.initials: R
authors.lastname: Kelsh
authors.forename: E
authors.initials: E
authors.lastname: Knapik
authors.forename: E
authors.initials: E
authors.lastname: Liao
authors.forename: B
authors.initials: B
authors.lastname: Paw
authors.forename: D
authors.initials: D
authors.lastname: Ransom
authors.forename: A
authors.initials: A
authors.lastname: Singer
authors.forename: M
authors.initials: M
authors.lastname: Thomson
authors.forename: T S
authors.initials: TS
authors.lastname: Abduljabbar
authors.forename: P
authors.initials: P
authors.lastname: Yelick
authors.forename: D
authors.initials: D
authors.lastname: Beier
authors.forename: J S
authors.initials: JS
authors.lastname: Joly
authors.forename: D
authors.initials: D
authors.lastname: Larhammar
authors.forename: F
authors.initials: F
authors.lastname: Rosa
authors.forename: M
authors.initials: M
authors.lastname: Westerfield
authors.forename: L I
authors.initials: LI
authors.lastname: Zon
authors.forename: S L
authors.initials: SL
authors.lastname: Johnson
authors.forename: W S
authors.initials: WS
authors.lastname: Talbot
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D019143:Evolution, Molecular; D005796:Genes / Q000235:genetics; D016678:Genome; D005810:Multigene Family; D011123:Polyploidy; D014714:Vertebrates / Q000235:genetics* / Q000502:physiology*; D015027:Zebrafish / Q000235:genetics*