title: Convergent evolution and orphan genes in the Fur4p-like family and characterization of a general nucleoside transporter in Aspergillus nidulans.
abstract: The function of seven paralogues phylogenetically related to the Saccharomyces cerevisiae Fur4p together with a number of functionally related transporters present in Aspergillus nidulans has been investigated. After deletion of the cognate genes we checked the incorporation of radiolabelled substrates, utilization of nitrogen sources, resistance to toxic analogues and supplementation of auxotrophies. FurA and FurD encode allantoin and uracil transporters respectively. No function was found for FurB, FurC, FurE, FurF and FurG. As we failed to identify Fur-related transporters for uridine, pyridoxine or thiamine, we deleted other possible candidates for these functions. A FCY2-like gene carrying in its 5' UTR a putative thiamine pyrophosphate riboswitch, and which encodes a protein similar to the pyridoxine transporter of yeast (Tpn1p), does not encode either a major thiamine or a pyridoxine transporter. CntA, a member of the concentrative nucleoside transporter family, is a general nucleoside permease, while no function was found for PnpA, a member of the equilibrative transporter family. Phylogenetic analysis shows that within the ascomycetes, the same transport activity could be catalysed by totally unrelated proteins and that within the Fur subfamily convergent evolution towards uracil and allantoin transport activity has occurred at least three and two independent times respectively.
authors.affiliation: Institut de Génétique et Microbiologie, UMR CNRS C8621, Université de Paris-XI, Centre d'Orsay, F-91405 Orsay Cedex, France.
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Hamari
authors.forename: Sotiris
authors.initials: S
authors.lastname: Amillis
authors.forename: Christine
authors.initials: C
authors.lastname: Drevet
authors.forename: Angeliki
authors.initials: A
authors.lastname: Apostolaki
authors.forename: Csaba
authors.initials: C
authors.lastname: Vágvölgyi
authors.forename: George
authors.initials: G
authors.lastname: Diallinas
authors.forename: Claudio
authors.initials: C
authors.lastname: Scazzocchio
mesh_terms: D001233:Aspergillus nidulans / Q000235:genetics* / Q000378:metabolism; D019143:Evolution, Molecular; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D005800:Genes, Fungal; D005810:Multigene Family; D033704:Nucleotide Transport Proteins / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D012331:RNA, Fungal / Q000235:genetics
chemical_list: D005656:Fungal Proteins; D033704:Nucleotide Transport Proteins; D012331:RNA, Fungal