MgAtr7, a new type of ABC transporter from Mycosphaerella graminicola involved in iron homeostasis

• Published in: Fungal genetics and biology Vol. 44; no. 9; pp. 853 - 863
• Main Authors: Zwiers, Lute-Harm, Roohparvar, Ramin, de Waard, Maarten A.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-09-2007
• Subjects: ABC transporter; ABC transporters; amino acid sequences; Ascomycota - genetics; Ascomycota - physiology; atp-binding cassette; ATP-Binding Cassette Transporters - genetics; ATP-Binding Cassette Transporters - metabolism; ATP-Binding Cassette Transporters - physiology; complementary DNA; Drug Resistance, Fungal - genetics; Drug Resistance, Fungal - physiology; filamentous fungi; Fungal Proteins - metabolism; Fungicide sensitivity; Fusarium graminearum; Gene Expression Regulation, Fungal; gene-cluster; genes; homeostasis; Homeostasis - physiology; iron; Iron - metabolism; major facilitator superfamily; MgAtr7 gene; molecular cloning; molecular sequence data; multidrug-resistance; Mycosphaerella graminicola; nucleotide sequences; Plant Diseases - microbiology; plant pathogenic fungi; Septoria tritici; Siderophore; siderophore biosynthesis; spore wall; toxic compounds; Triticum aestivum; virulence; wheat; Iron metabolism; Septoria tritici; Mycosphaerella graminicola; Siderophore; Fungicide sensitivity; ABC transporter
• ISSN: 1087-1845; 1096-0937
• DOI: 10.1016/j.fgb.2007.02.001

The ABC transporter-encoding gene
MgAtr7 from the wheat pathogen
Mycosphaerella graminicola was cloned based upon its high homology to ABC transporters involved in azole-fungicide sensitivity. Genomic and cDNA sequences indicated that the N-terminus of this ABC transporter contains a motif characteristic for a dityrosine/pyoverdine biosynthesis protein. This makes MgAtr7 the first member of a new class of fungal ABC transporters harboring both a transporter and a biosynthetic moiety. A homologue of
MgAtr7 containing the same biosynthetic moiety was only found in the
Fusarium graminearum genome and not in any other fungal genome examined so far. The gene structure of both orthologous transporters is highly conserved and the genomic area surrounding the ABC transporter exhibits micro-synteny between
M.
graminicola and
F. graminearum. Functional analyses revealed that MgAtr7 is neither required for virulence nor involved in fungicide sensitivity but indicated a role in maintenance of iron homeostasis.