Format

Send to

Choose Destination
See comment in PubMed Commons below
Integr Comp Biol. 2010 Dec;50(6):1009-17. doi: 10.1093/icb/icq071. Epub 2010 Jul 12.

Antarctic notothenioid fishes: genomic resources and strategies for analyzing an adaptive radiation.

Author information

1
Department of Biology, Northeastern University, Boston, MA 02115, USA. iceman@neu.edu

Abstract

The perciform suborder Notothenoidei provides a compelling opportunity to study the adaptive radiation of a marine species-flock in the cold Southern Ocean that surrounds Antarctica. To facilitate genome-level studies of the diversification of these fishes, we present estimates of the genome sizes of 11 Antarctic species and describe the production of high-quality bacterial artificial chromosome (BAC) libraries for two, the red-blooded notothen Notothenia coriiceps and the white-blooded icefish Chaenocephalus aceratus. Our results indicate that evolution of phylogenetically derived notothenioid families (e.g., the crown group Channichthyidae [icefishes]), was accompanied by genome expansion. Six species from the basal family Nototheniidae had C-values between 0.98 and 1.20 pg, a range that is consistent with the genome sizes of proposed outgroups (e.g., percids) of the notothenioid suborder. In contrast, four icefishes had C-values in the range 1.66-1.83 pg. The BAC libraries VMRC-19 (N. coriiceps) and VMRC-21 (C. aceratus) comprise 12× and 10× coverage of the respective genomes and have average insert sizes of 138 and 168 kb. Paired BAC-end reads representing ∼0.1% of each genome showed that the repetitive element landscapes of the two genomes (13.4% of the N. coriiceps genome and 14.5% for C. aceratus) were similar. The availability of these high-quality and well-characterized BAC libraries sets the stage for targeted genomic analyses of the unusual anatomical and physiological adaptations of the notothenioids, some of which mimic human diseases. Here we consider the evolution of secondary pelagicism by various taxa of the group and illustrate the utility of Antarctic icefishes as an evolutionary-mutant model of human osteopenia (low-mineral density of bones).

PMID:
21082069
PMCID:
PMC2981591
DOI:
10.1093/icb/icq071
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Silverchair Information Systems Icon for PubMed Central
    Loading ...
    Support Center