title: Widespread horizontal transfer of the cerato-ulmin gene between Ophiostoma novo-ulmi and Geosmithia species.
abstract: Previous work had shown that a sequence homologous to the gene encoding class II hydrophobin cerato-ulmin from the fungus Ophiostoma novo-ulmi, the causal agent of Dutch Elm Disease (DED), was present in a strain of the unrelated species Geosmithia species 5 (Ascomycota: Hypocreales) isolated from Ulmus minor affected by DED. As both fungi occupy the same habitat, even if different ecological niches, the occurrence of horizontal gene transfer was proposed. In the present work we have analysed for the presence of the cerato-ulmin gene 70 Geosmithia strains representing 29 species, isolated from different host plants and geographic locations. The gene was found in 52.1 % of the strains derived from elm trees, while none of those isolated from nonelms possessed it. The expression of the gene in Geosmithia was also assessed by real time PCR in different growth conditions (liquid culture, solid culture, elm sawdust, dual culture with O. novo-ulmi), and was found to be extremely low in all conditions tested. On the basis of these results we propose that the cerato-ulmin gene is not functional in Geosmithia, but can be considered instead a marker of more extensive transfers of genetic material as shown in other fungi.
authors.affiliation: Dipartimento di Biologia, Università di Firenze, via Madonna del Piano 6, 50019 Sesto Fiorentino (FI), Italy. Electronic address: p.bettini@unifi.it.
authors.forename: Priscilla P
authors.initials: PP
authors.lastname: Bettini
authors.affiliation: Dipartimento di Biologia, Università di Firenze, via Madonna del Piano 6, 50019 Sesto Fiorentino (FI), Italy; Dipartimento di Scienze delle Produzioni Agroalimentari e dell'Ambiente (DISPAA), Università di Firenze, via della Lastruccia 10, 50019 Sesto Fiorentino (FI), Italy. Electronic address: affabula@gmail.com.
authors.forename: Arcangela
authors.initials: A
authors.lastname: Frascella
authors.affiliation: Institute of Microbiology of the Academy of Sciences of the Czech Republic (ASCR), v.v.i, Videnská 1083, 142 20 Praha 4, Czech Republic; Department of Botany, Faculty of Science, Charles University, Benatská 2, 128 01 Praha 2, Czech Republic. Electronic address: mkolarik@biomed.cas.cz.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Kolařík
authors.affiliation: Dipartimento di Scienze delle Produzioni Agroalimentari e dell'Ambiente (DISPAA), Università di Firenze, via della Lastruccia 10, 50019 Sesto Fiorentino (FI), Italy. Electronic address: cecilia.comparini@unifi.it.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Comparini
authors.affiliation: Istituto per la Protezione delle Piante, Consiglio Nazionale delle Ricerche (IPP-CNR), via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy. Electronic address: a.pepori@ipp.cnr.it.
authors.forename: Alessia L
authors.initials: AL
authors.lastname: Pepori
authors.affiliation: Istituto per la Protezione delle Piante, Consiglio Nazionale delle Ricerche (IPP-CNR), via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy. Electronic address: a.santini@ipp.cnr.it.
authors.forename: Alberto
authors.initials: A
authors.lastname: Santini
authors.affiliation: Dipartimento di Arboricoltura, Botanica e Patologia Vegetale, Sezione di Patologia Vegetale, Università di Napoli "Federico II", via Università 100, 80055 Portici (NA), Italy. Electronic address: felice.scala@unina.it.
authors.forename: Felice
authors.initials: F
authors.lastname: Scala
authors.affiliation: Dipartimento di Scienze delle Produzioni Agroalimentari e dell'Ambiente (DISPAA), Università di Firenze, via della Lastruccia 10, 50019 Sesto Fiorentino (FI), Italy. Electronic address: aniello.scala@unifi.it.
authors.forename: Aniello
authors.initials: A
authors.lastname: Scala
mesh_terms: D001203:Ascomycota / Q000235:genetics* / Q000302:isolation & purification; D005656:Fungal Proteins / Q000235:genetics*; D020869:Gene Expression Profiling; D022761:Gene Transfer, Horizontal; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D009183:Mycotoxins / Q000235:genetics*; D010935:Plant Diseases / Q000382:microbiology; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D034403:Ulmus / Q000382:microbiology
chemical_list: D005656:Fungal Proteins; D009183:Mycotoxins; C079060:CU protein, Ophiostoma ulmi
keywords: Ascomycetes; Entomochoric fungi; Gene expression; Horizontal gene transfer; Hydrophobins