Testing for Natural Selection in Human Exonic Splicing Regulators Associated with Evolutionary Rate Shifts

Despite evidence that at the interspecific scale, exonic splicing silencers (ESSs) are under negative selection in constitutive exons, little is known about the effects of slightly deleterious polymorphisms on these splicing regulators. Through the application of a modified version of the McDonald–K...

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Detalhes bibliográficos
Autores: Ramalho, Rodrigo F., Gelfman, Sahar, Souza, Jorge E. de, Ast, Gil, Souza, Sandro José de, Meyer, Diogo
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2013
País:Brasil
Recursos:Universidade Federal do Rio Grande do Norte (UFRN)
Repositorio:Repositório Institucional da UFRN
Idioma:inglés
OAI Identifier:oai:repositorio.ufrn.br:123456789/23332
Acesso em linha:https://repositorio.ufrn.br/jspui/handle/123456789/23332
Access Level:acceso abierto
Palavra-chave:Alternative splicing
Human polymorphism
Exonic splicing regulators
MK test
Descrição
Resumo:Despite evidence that at the interspecific scale, exonic splicing silencers (ESSs) are under negative selection in constitutive exons, little is known about the effects of slightly deleterious polymorphisms on these splicing regulators. Through the application of a modified version of the McDonald–Kreitman test, we compared the normalized proportions of human polymorphisms and human/rhesus substitutions affecting exonic splicing regulators (ESRs) on sequences of constitutive and alternative exons. Our results show a depletion of substitutions and an enrichment of SNPs associated with ESS gain in constitutive exons. Moreover, we show that this evolutionary pattern is also present in a set of ESRs previously involved in the transition from constitutive to skipped exons in the mammalian lineage. The similarity between these two sets of ESRs suggests that the transition from constitutive to skipped exons in mammals is more frequently associated with the inhibition than with the promotion of splicing signals. This is in accordance with the hypothesis of a constitutive origin of exon skipping and corroborates previous findings about the antagonistic role of certain exonic splicing enhancers.