INVESTIGADORES
BELLORA nicolas
artículos
Título:
Origin of Primate Orphan Genes: A Comparative Genomics Approach
Autor/es:
MACARENA TOLL-RIERA; NINA BOSCH; NICOLAS BELLORA; ROBERT CASTELO; LLUIS ARMENGOL; XAVIER ESTIVILL; M. MAR ALBA
Revista:
MOLECULAR BIOLOGY AND EVOLUTION
Editorial:
OXFORD UNIV PRESS
Referencias:
Lugar: Oxford; Año: 2008 vol. 23 p. 603 - 612
ISSN:
0737-4038
Resumen:
Genomes contain a large number of genes that do not have recognizable
homologues in other species and that are likely to be involved in
important species-specific adaptive processes. The origin of many such
"orphan" genes remains unknown. Here we present the first systematic
study of the characteristics and mechanisms of formation of
primate-specific orphan genes. We determine that codon usage values for
most orphan genes fall within the bulk of the codon usage distribution
of bona fide human proteins, supporting their current protein-coding
annotation. We also show that primate orphan genes display distinctive
features in relation to genes of wider phylogenetic distribution:
higher tissue specificity, more rapid evolution, and shorter peptide
size. We estimate that around 24% are highly divergent members of
mammalian protein families. Interestingly, around 53% of the orphan
genes contain sequences derived from transposable elements (TEs) and
are mostly located in primate-specific genomic regions. This indicates
frequent recruitment of TEs as part of novel genes. Finally, we also
obtain evidence that a small fraction of primate orphan genes, around
5.5%, might have originated de novo from mammalian noncoding genomic
regions.