title: The Origin and Diversity of Cpt1 Genes in Vertebrate Species.
abstract: The Carnitine palmitoyltransferase I (Cpt1) gene family plays a crucial role in energy homeostasis since it is required for the occurrence of fatty acid β-oxidation in the mitochondria. The exact gene repertoire in different vertebrate lineages is variable. Presently, four genes are documented: Cpt1a, also known as Cpt1a1, Cpt1a2; Cpt1b and Cpt1c. The later is considered a mammalian innovation resulting from a gene duplication event in the ancestor of mammals, after the divergence of sauropsids. In contrast, Cpt1a2 has been found exclusively in teleosts. Here, we reassess the overall evolutionary relationships of Cpt1 genes using a combination of approaches, including the survey of the gene repertoire in basal gnathostome lineages. Through molecular phylogenetics and synteny studies, we find that Cpt1c is most likely a rapidly evolving orthologue of Cpt1a2. Thus, Cpt1c is present in other lineages such as cartilaginous fish, reptiles, amphibians and the coelacanth. We show that genome duplications (2R) and variable rates of sequence evolution contribute to the history of Cpt1 genes in vertebrates. Finally, we propose that loss of Cpt1b is the likely cause for the unusual energy metabolism of elasmobranch.
authors.affiliation: CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associate Laboratory, UPorto-University of Porto, Porto, Portugal; ICBAS, Abel Salazar Biomedical Sciences Institute, University of Porto, Porto, Portugal.
authors.forename: Mónica
authors.initials: M
authors.lastname: Lopes-Marques
authors.affiliation: CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associate Laboratory, UPorto-University of Porto, Porto, Portugal.
authors.forename: Inês L S
authors.initials: IL
authors.lastname: Delgado
authors.affiliation: CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associate Laboratory, UPorto-University of Porto, Porto, Portugal.
authors.forename: Raquel
authors.initials: R
authors.lastname: Ruivo
authors.affiliation: CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associate Laboratory, UPorto-University of Porto, Porto, Portugal; ICBAS, Abel Salazar Biomedical Sciences Institute, University of Porto, Porto, Portugal.
authors.forename: Yan
authors.initials: Y
authors.lastname: Torres
authors.affiliation: CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associate Laboratory, UPorto-University of Porto, Porto, Portugal.
authors.forename: Sri Bhashyam
authors.initials: SB
authors.lastname: Sainath
authors.affiliation: CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associate Laboratory, UPorto-University of Porto, Porto, Portugal; ICBAS, Abel Salazar Biomedical Sciences Institute, University of Porto, Porto, Portugal.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Rocha
authors.affiliation: CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associate Laboratory, UPorto-University of Porto, Porto, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Cunha
authors.affiliation: CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associate Laboratory, UPorto-University of Porto, Porto, Portugal; Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal.
authors.forename: Miguel M
authors.initials: MM
authors.lastname: Santos
authors.affiliation: CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associate Laboratory, UPorto-University of Porto, Porto, Portugal; Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal.
authors.forename: L Filipe C
authors.initials: LF
authors.lastname: Castro
mesh_terms: D000818:Animals; D002334:Carnitine O-Palmitoyltransferase / Q000235:genetics*; D004734:Energy Metabolism / Q000502:physiology; D019143:Evolution, Molecular; D006801:Humans; D010802:Phylogeny
chemical_list: D002334:Carnitine O-Palmitoyltransferase