Amino-acid alterations in the beta-tubulin gene of Neurospora crassa that confer resistance to carbendazim and diethofencarb.
We have previously shown that increased sensitivity to diethofencarb in the carbendazim(MBC)-resistant F914 strain of Neurospora crassa is caused by a single amino-acid change in beta-tubulin, 198Glu to Gly. Three diethofencarb-resistant mutants that are also resistant to MBC were isolated from strain F914. They contained single base-pair-substitution mutations in the beta-tubulin gene. The amino acid changes in beta-tubulin, Phe from 250Leu, Val from 165Ala, and Ala from 237Thr, were responsible for diethofencarb-resistance in the mutant strains FR511, FR513, and FR421, respectively. The amino acid at position 198 of beta-tubulin in these mutants was Gly, which is the same as in strain F914. beta-tubulin genes with 198Glu were constructed by site-directed mutagenesis. The altered beta-tubulin genes derived from FR511 and FR421 transformed the wild-type strain to resistance to MBC, indicating that 250Phe and 237Ala in beta-tubulin are responsible for resistance not only to diethofencarb but also to MBC.
Fujimura
M
M
Takarazuka Research Center, Sumitomo Chemical Company Ltd., Hyogo, Japan.
Kamakura
T
T
Inoue
H
H
Yamaguchi
I
I
D000595:Amino Acid Sequence; D001483:Base Sequence; D001562:Benzimidazoles / Q000494:pharmacology; D002219:Carbamates / Q000494:pharmacology; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics; D004352:Drug Resistance, Microbial / Q000235:genetics; D005659:Fungicides, Industrial / Q000494:pharmacology; D005800:Genes, Fungal / Q000187:drug effects; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009492:Neurospora crassa / Q000187:drug effects / Q000235:genetics*; D048448:Phenylcarbamates; D014404:Tubulin / Q000235:genetics*
D001562:Benzimidazoles; D002219:Carbamates; D017931:DNA Primers; D004271:DNA, Fungal; D005659:Fungicides, Industrial; D048448:Phenylcarbamates; D014404:Tubulin; C070961:diethofencarb; C006698:carbendazim