title: Critical roles for a genetic code alteration in the evolution of the genus Candida.
abstract: During the last 30 years, several alterations to the standard genetic code have been discovered in various bacterial and eukaryotic species. Sense and nonsense codons have been reassigned or reprogrammed to expand the genetic code to selenocysteine and pyrrolysine. These discoveries highlight unexpected flexibility in the genetic code, but do not elucidate how the organisms survived the proteome chaos generated by codon identity redefinition. In order to shed new light on this question, we have reconstructed a Candida genetic code alteration in Saccharomyces cerevisiae and used a combination of DNA microarrays, proteomics and genetics approaches to evaluate its impact on gene expression, adaptation and sexual reproduction. This genetic manipulation blocked mating, locked yeast in a diploid state, remodelled gene expression and created stress cross-protection that generated adaptive advantages under environmental challenging conditions. This study highlights unanticipated roles for codon identity redefinition during the evolution of the genus Candida, and strongly suggests that genetic code alterations create genetic barriers that speed up speciation.
authors.affiliation: Department of Biology and CESAM, University of Aveiro, Aveiro, Portugal.
authors.forename: Raquel M
authors.initials: RM
authors.lastname: Silva
authors.forename: João A
authors.initials: JA
authors.lastname: Paredes
authors.forename: Gabriela R
authors.initials: GR
authors.lastname: Moura
authors.forename: Bruno
authors.initials: B
authors.lastname: Manadas
authors.forename: Tatiana
authors.initials: T
authors.lastname: Lima-Costa
authors.forename: Rita
authors.initials: R
authors.lastname: Rocha
authors.forename: Isabel
authors.initials: I
authors.lastname: Miranda
authors.forename: Ana C
authors.initials: AC
authors.lastname: Gomes
authors.forename: Marian J G
authors.initials: MJ
authors.lastname: Koerkamp
authors.forename: Michel
authors.initials: M
authors.lastname: Perrot
authors.forename: Frank C P
authors.initials: FC
authors.lastname: Holstege
authors.forename: Hélian
authors.initials: H
authors.lastname: Boucherie
authors.forename: Manuel A S
authors.initials: MA
authors.lastname: Santos
mesh_terms: D001483:Base Sequence; D002175:Candida / Q000235:genetics*; D005800:Genes, Fungal; D005815:Genetic Code; D005821:Genetic Techniques; D016681:Genome, Fungal; D023281:Genomics; D008239:Lysine / Q000031:analogs & derivatives / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation; D009690:Nucleic Acid Conformation; D020411:Oligonucleotide Array Sequence Analysis; D040901:Proteomics; D012441:Saccharomyces cerevisiae / Q000235:genetics; D017279:Selenocysteine / Q000235:genetics
chemical_list: D017279:Selenocysteine; C456839:pyrrolysine; D008239:Lysine