title: Integration of the genetic map and genome assembly of fugu facilitates insights into distinct features of genome evolution in teleosts and mammals.
abstract: The compact genome of fugu (Takifugu rubripes) has been used widely as a reference genome for understanding the evolution of vertebrate genomes. However, the fragmented nature of the fugu genome assembly has restricted its use for comparisons of genome architecture in vertebrates. To extend the contiguity of the assembly to the chromosomal level, we have generated a comprehensive genetic map of fugu and anchored the scaffolds of the assembly to the 22 chromosomes of fugu. The map consists of 1,220 microsatellite markers that provide anchor points to 697 scaffolds covering 86% of the genome assembly (http://www.fugu-sg.org/). The integrated genome map revealed a higher recombination rate in fugu compared with other vertebrates and a wide variation in the recombination rate between sexes and across chromosomes of fugu. We used the extended assembly to explore recent rearrangement events in the lineages of fugu, Tetraodon, and medaka and compared them with rearrangements in three mammalian (human, mouse, and opossum) lineages. Between the two pufferfishes, fugu has experienced fewer chromosomal rearrangements than Tetraodon. The gene order is more highly conserved in the three teleosts than in mammals largely due to a lower rate of interchromosomal rearrangements in the teleosts. These results provide new insights into the distinct patterns of genome evolution between teleosts and mammals. The consolidated genome map and the genetic map of fugu are valuable resources for comparative genomics of vertebrates and for elucidating the genetic basis of the phenotypic diversity of ~25 species of Takifugu that evolved within the last 5 My.
authors.affiliation: Fisheries Laboratory, Graduate School of Agricultural and Life Sciences, University of Tokyo, Hamamatsu, Shizuoka, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Kai
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Kikuchi
authors.forename: Sumanty
authors.initials: S
authors.lastname: Tohari
authors.forename: Ah Keng
authors.initials: AK
authors.lastname: Chew
authors.forename: Alice
authors.initials: A
authors.lastname: Tay
authors.forename: Atushi
authors.initials: A
authors.lastname: Fujiwara
authors.forename: Sho
authors.initials: S
authors.lastname: Hosoya
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Suetake
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Naruse
authors.forename: Sydney
authors.initials: S
authors.lastname: Brenner
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Byrappa
authors.initials: B
authors.lastname: Venkatesh
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D002875:Chromosomes; D017124:Conserved Sequence / Q000235:genetics; D019143:Evolution, Molecular; D023061:Gene Order; D015321:Gene Rearrangement; D016678:Genome; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008322:Mammals / Q000235:genetics*; D051379:Mice; D018895:Microsatellite Repeats; D009893:Opossums / Q000235:genetics; D009990:Oryzias / Q000235:genetics; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D023741:Takifugu / Q000235:genetics*; D023721:Tetraodontiformes / Q000235:genetics