Publication Detail

The cytochrome P450 genesis locus: the origin and evolution of animal cytochrome P450s

David R. Nelson, Jared V. Goldstone, John J. Stegeman
23 pp.
MITSG 13-06
$5.50 DOM / $7.50 INT

The neighbourhoods of cytochrome P450 (CYP) genes in deuterostome genomes,
as well as those of the cnidarians Nematostella vectensis and Acropora
digitifera and the placozoan Trichoplax adhaerens were examined to find
clues concerning the evolution of CYP genes in animals. CYP genes created
by the 2R whole genome duplications in chordates have been identified.
Both microsynteny and macrosynteny were used to identify genes that coexisted
near CYP genes in the animal ancestor. We show that all 11 CYP clans
began in a common gene environment. The evidence implies the existence of
a single locus, which we term the ‘cytochrome P450 genesis locus’, where
one progenitor CYP gene duplicated to create a tandem set of genes that
were precursors of the 11 animal CYP clans: CYP Clans 2, 3, 4, 7, 19, 20,
26, 46, 51, 74 and mitochondrial. These early CYP genes existed side by
side before the origin of cnidarians, possibly with a few additional genes
interspersed. The Hox gene cluster, WNT genes, an NK gene cluster and at
least one ARF gene were close neighbours to this original CYP locus. According
to this evolutionary scenario, the CYP74 clan originated from animals
and not from land plants nor from a common ancestor of plants and animals.
The CYP7 and CYP19 families that are chordate-specific belong to CYP clans
that seem to have originated in the CYP genesis locus as well, even though
this requires many gene losses to explain their current distribution. The
approach to uncovering the CYP genesis locus overcomes confounding
effects because of gene conversion, sequence divergence, gene birth and
death, and opens the way to understanding the biodiversity of CYP genes,
families and subfamilies, which in animals has been obscured by more
than 600 Myr of evolution.

type: Journal, book, proceeding reprints

Parent Project

Project No.: 2010-R/RCM-28
Title: Active samplers: development of biomarkers for coastal pollution in the blue mussel, Mytilus edulis