The evolution of the heat-shock protein GroEL from <i>Buchnera</i>, the primary endosymbiont of aphids, is governed by positive selection

The heat-shock protein GroEL is a double-ring-structured chaperonin that assists the folding of many newly synthesized proteins in Escherichia coli and the refolding in vitro, with the cochaperonin GroES, of con damaged proteins. This protein is constitutively overexpressed in the primary symbiotic...

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Detalles Bibliográficos
Autores: Fares, MA, Barrio, E, Sabater-Muñoz, B, Moya, A
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2002
País:España
Institución:Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana (FISABIO)
Repositorio:r-FISABIO. Repositorio Institucional de Producción Científica
OAI Identifier:oai:fisabio.fundanetsuite.com:p17225
Acceso en línea:https://fisabio.portalinvestigacion.com/publicaciones/17225
Access Level:acceso abierto
Palabra clave:aphid endosymbionts
Buchnera aphidicola
groEL
positive selection
rates of evolution
Descripción
Sumario:The heat-shock protein GroEL is a double-ring-structured chaperonin that assists the folding of many newly synthesized proteins in Escherichia coli and the refolding in vitro, with the cochaperonin GroES, of con damaged proteins. This protein is constitutively overexpressed in the primary symbiotic bacteria of many insects. constituting approximately 10% of the total protein in Buchnera. the primary endosymbiont of aphids. In the present study, we perform a maximum likelihood (ML) analysis to unveil the selective constraints in GroEL. In addition. we apply a new statistical approach to determine the patterns of evolution in this highly interesting protein. The main conclusion derived from our analysis is that GroEL has Suffered an accelerated rate of amino acid Substitution upon the symbiotic integration of Buchnera into the aphids. It is most interesting that the ML analysis of codon substitutions in the different branches of the phylogenetic tree strongly Supports the action of positive selection in the different lineages of Buchnera. Additionally. the new sliding window analysis of the complete groEL sequence reveals different re-ions of the molecule Under the action of positive selection. mainly located in the apical domain, that are important for both peptide and GroES binding.