title: Characterization of purine catabolic pathway genes in coelacanths.
abstract: Coelacanths are a critically valuable species to explore the gene changes that took place in the transition from aquatic to terrestrial life. One interesting and biologically relevant feature of the genus Latimeria is ureotelism. However not all urea is excreted from the body; in fact high concentrations are retained in plasma and seem to be involved in osmoregulation. The purine catabolic pathway, which leads to urea production in Latimeria, has progressively lost some steps, reflecting an enzyme loss during diversification of terrestrial species. We report the results of analyses of the liver and testis transcriptomes of the Indonesian coelacanth Latimeria menadoensis and of the genome of Latimeria chalumnae, which has recently been fully sequenced in the framework of the coelacanth genome project. We describe five genes, uricase, 5-hydroxyisourate hydrolase, parahox neighbor B, allantoinase, and allantoicase, each coding for one of the five enzymes involved in urate degradation to urea, and report the identification of a putative second form of 5-hydroxyisourate hydrolase that is characteristic of the genus Latimeria. The present data also highlight the activity of the complete purine pathway in the coelacanth liver and suggest its involvement in the maintenance of high plasma urea concentrations.
authors.affiliation: Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, Italy.
authors.forename: Mariko
authors.initials: M
authors.lastname: Forconi
authors.forename: Maria Assunta
authors.initials: MA
authors.lastname: Biscotti
authors.forename: Marco
authors.initials: M
authors.lastname: Barucca
authors.forename: Francesco
authors.initials: F
authors.lastname: Buonocore
authors.forename: Gianluca
authors.initials: G
authors.lastname: De Moro
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Fausto
authors.forename: Marco
authors.initials: M
authors.lastname: Gerdol
authors.forename: Alberto
authors.initials: A
authors.lastname: Pallavicini
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Scapigliati
authors.forename: Manfred
authors.initials: M
authors.lastname: Schartl
authors.forename: Ettore
authors.initials: E
authors.lastname: Olmo
authors.forename: Adriana
authors.initials: A
authors.lastname: Canapa
mesh_terms: D000581:Amidohydrolases / Q000235:genetics; D000818:Animals; D019143:Evolution, Molecular; D005399:Fishes / Q000235:genetics* / Q000378:metabolism*; D005796:Genes; D006867:Hydrolases / Q000235:genetics; D008099:Liver / Q000378:metabolism; D008297:Male; D011687:Purines / Q000378:metabolism*; D013737:Testis / Q000378:metabolism; D059467:Transcriptome; D014503:Urate Oxidase / Q000235:genetics; D014512:Ureohydrolases / Q000378:metabolism
chemical_list: D011687:Purines; D014503:Urate Oxidase; D006867:Hydrolases; D000581:Amidohydrolases; C019659:allantoinase; D014512:Ureohydrolases; C019658:allantoicase; C030985:purine