Targeted disruption of a G protein alpha subunit gene results in reduced pathogenicity in Fusarium oxysporum.
The cloning of fga1, the gene encoding a G protein alpha subunit, was performed by standard PCR techniques and by screening a Fusarium oxysporum genomic library, using the PCR product as a probe. The full-length open reading frame spanned 1,059 nucleotides and the deduced primary structure of the protein (353 amino acid residues) showed high identity to those of G protein alpha(i) family proteins from other filamentous fungi. Disruption of fga1 had no effect on vegetative growth, but reduced the conidiation and pathogenicity of the fungus. Disruptants also showed a decreased level of intracellular cAMP and increased resistance to heat shock at 45 degrees C. These results suggest that the Galpha subunit encoded by fga1 is involved in a signal transduction pathway in F. oxysporum that controls conidiation, heat resistance and pathogenicity.
Jain
Sona
S
Department of Applied Life Science, Faculty of Agriculture, Ehime University, Matsuyama 790-8566, Japan.
Akiyama
Kouichi
K
Mae
Kenjiro
K
Ohguchi
Tomizo
T
Takata
Renkichi
R
D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D005670:Fusarium / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology; D006360:Heat-Shock Proteins / Q000235:genetics; D020962:Heterotrimeric GTP-Binding Proteins / Q000235:genetics* / Q000502:physiology; D006358:Hot Temperature; D008969:Molecular Sequence Data; D010935:Plant Diseases / Q000382:microbiology; D016133:Polymerase Chain Reaction; D014158:Transcription, Genetic
D006360:Heat-Shock Proteins; D020962:Heterotrimeric GTP-Binding Proteins