Lancelets ('amphioxus') are the modern survivors of an ancient chordate lineage, with a fossil record dating back to the Cambrian period. Here we describe the structure and gene content of the highly polymorphic approximately 520-megabase genome of the Florida lancelet Branchiostoma floridae, and analyse it in the context of chordate evolution. Whole-genome comparisons illuminate the murky relationships among the three chordate groups (tunicates, lancelets and vertebrates), and allow not only reconstruction of the gene complement of the last common chordate ancestor but also partial reconstruction of its genomic organization, as well as a description of two genome-wide duplications and subsequent reorganizations in the vertebrate lineage. These genome-scale events shaped the vertebrate genome and provided additional genetic variation for exploitation during vertebrate evolution.

Original publication

DOI

10.1038/nature06967

Type

Journal article

Journal

Nature

Publication Date

19/06/2008

Volume

453

Pages

1064 - 1071

Keywords

Animals, Chordata, Conserved Sequence, DNA Transposable Elements, Evolution, Molecular, Gene Duplication, Genes, Genetic Linkage, Genome, Humans, Introns, Karyotyping, Multigene Family, Phylogeny, Polymorphism, Genetic, Proteins, Synteny, Time Factors, Vertebrates