Dissemin is shutting down on January 1st, 2025

Published in

Elsevier, Molecular Phylogenetics and Evolution, 2(62), p. 708-717, 2012

DOI: 10.1016/j.ympev.2011.11.013

Links

Tools

Export citation

Search in Google Scholar

Peculiar patterns of amino acid substitution and conservation in the fast evolving tunicate Oikopleura dioica

Journal article published in 2011 by Luisa Berná, Giuseppe D'Onofrio, Fernando Alvarez-Valin ORCID
This paper is available in a repository.
This paper is available in a repository.

Full text: Download

Green circle
Preprint: archiving allowed
Orange circle
Postprint: archiving restricted
Red circle
Published version: archiving forbidden
Data provided by SHERPA/RoMEO

Abstract

We analyze the patterns and rates of amino acid evolution in tunicates with special interest on the extremely fast evolving Oikopleura dioica. We show that this species, on average, is twice as fast as the already fast evolving Ciona intestinalis. The acceleration in both species seems to be affected by similar evolutionary forces yet to different extent, since a substantial proportion of the most and less accelerated genes are orthologous between the two species. Among the possible causes that underlie the genome wide acceleration in Oikopleura, relaxation of functional constraints appears to be an important one, since all amino acids exhibit surprisingly homogenous levels of divergence. Such homogeneity, however, is not observed in Ciona. Apart from the genome wide acceleration, detailed analysis of functional groups of genes revealed that genes associated with regulatory functions (transcription regulators, chromatin remodeling proteins and metabolic regulators), have been subjected to an even more extreme process of acceleration, suggesting that adaptive evolution is the most probable cause of their unusual exacerbated rates. Another remarkable observation is that cysteine is among the less conserved amino acids, contrary to what is commonly observed in other species. The possible causes of this particular behavior are discussed.