Overexpression of a cell wall glycoprotein in Fusarium oxysporum increases virulence and resistance to a plant PR-5 protein.
Fusarium oxysporum f. sp. nicotianae is a causal agent for vascular wilt disease in tobacco. It is sensitive to osmotin, a tobacco pathogenesis-related protein (PR-5) that is implicated in plant defense against phytopathogenic fungi. We show that osmotin susceptibility of F. oxysporum f. sp. nicotianae was reduced by overexpression of the heterologous cell wall glycoprotein Saccharomyces cerevisiae protein containing inverted repeats (PIR2), a member of the PIR family of fungal cell wall glycoproteins that protect S. cerevisiae from the toxic action of osmotin. S. cerevisiae PIR2 was targeted to the cell wall of F. oxysporum. Disease severity and fungal growth were increased in tobacco seedlings inoculated with F. oxysporum transformed with PIR2 compared to seedlings infected with untransformed F. oxysporum or that transformed with vector, although accumulation of transcript and protein of defense genes was similar. The results show that fungal cell wall components can increase resistance to plant defense proteins and affect virulence.
Narasimhan
Meena L
ML
Center for Plant Environmental Stress Physiology, 625 Agriculture Mall Drive, Purdue University, West Lafayette, IN 47907-2010, USA. narsimhan@hort.purdue.edu
Lee
Hyeseung
H
Damsz
Barbara
B
Singh
Narendra K
NK
Ibeas
José I
JI
Matsumoto
Tracie K
TK
Woloshuk
Charles P
CP
Bressan
Ray A
RA
D002473:Cell Wall / Q000235:genetics*; D005656:Fungal Proteins / Q000235:genetics*; D005670:Fusarium / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity*; D015966:Gene Expression Regulation, Fungal; D018525:Germination; D007113:Immunity, Innate; D008562:Membrane Glycoproteins / Q000235:genetics*; D010935:Plant Diseases / Q000382:microbiology*; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012639:Seeds / Q000502:physiology; D014026:Nicotiana / Q000254:growth & development / Q000382:microbiology*; D014774:Virulence
D005656:Fungal Proteins; D008562:Membrane Glycoproteins