The drug transporter MgMfs1 can modulate sensitivity of field strains of the fungal wheat pathogen Mycosphaerella graminicola to the strobilurin fungicide trifloxystrobin.
BACKGROUND
The major facilitator superfamily (MFS) drug transporter MgMfs1 of the wheat pathogen Mycosphaerella graminicola (Fuckel) J Schroeter is a potent multidrug transporter with high capacity to transport strobilurin fungicides in vitro. The data presented in this paper indicate that, in addition to the predominant cause of strobilurin resistance, cytochrome b G143A subsititution, MgMfs1 can play a role in sensitivity of field strains of this pathogen to trifloxystrobin.


RESULTS
In a major part of field strains of M. graminicola (collected in the Netherlands in 2004) containing the cytochrome b G143A substitution, the basal level of expression of MgMfs1 was elevated as compared with sensitive strains lacking the G143A substitution. Induction of MgMfs1 expression in wild-type isolates upon treatment with trifloxystrobin at sublethal concentrations proceeded rapidly. Furthermore, in disease control experiments on wheat seedlings, disruption mutants of MgMfs1 displayed an increased sensitivity to trifloxystrobin.


CONCLUSIONS
It is concluded that the drug transporter MgMfs1 is a determinant of strobilurin sensitivity of field strains of M. graminicola.
Roohparvar
Ramin
R
Laboratory of Phytopathology, Wageningen University, PO Box 8025, 6700 EE Wageningen, The Netherlands.
Mehrabi
Rahim
R
Van Nistelrooy
Johannes G M
JG
Zwiers
Lute-Harm
LH
De Waard
Maarten A
MA
D000085:Acetates / Q000378:metabolism / Q000494:pharmacology*; D019943:Amino Acid Substitution; D001203:Ascomycota / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D003573:Cytochrome b Group / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005659:Fungicides, Industrial / Q000378:metabolism / Q000494:pharmacology*; D007097:Imines / Q000378:metabolism / Q000494:pharmacology*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D008689:Methacrylates / Q000378:metabolism / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D009154:Mutation; D010935:Plant Diseases / Q000382:microbiology*; D000073739:Strobilurins; D014908:Triticum / Q000187:drug effects / Q000382:microbiology*
D000085:Acetates; D003573:Cytochrome b Group; D005656:Fungal Proteins; D005659:Fungicides, Industrial; D007097:Imines; D026901:Membrane Transport Proteins; D008689:Methacrylates; D000073739:Strobilurins; C467051:trifloxystrobin