The nuclear protein Sge1 of Fusarium oxysporum is required for parasitic growth.
Dimorphism or morphogenic conversion is exploited by several pathogenic fungi and is required for tissue invasion and/or survival in the host. We have identified a homolog of a master regulator of this morphological switch in the plant pathogenic fungus Fusarium oxysporum f. sp. lycopersici. This non-dimorphic fungus causes vascular wilt disease in tomato by penetrating the plant roots and colonizing the vascular tissue. Gene knock-out and complementation studies established that the gene for this putative regulator, SGE1 (SIX Gene Expression 1), is essential for pathogenicity. In addition, microscopic analysis using fluorescent proteins revealed that Sge1 is localized in the nucleus, is not required for root colonization and penetration, but is required for parasitic growth. Furthermore, Sge1 is required for expression of genes encoding effectors that are secreted during infection. We propose that Sge1 is required in F. oxysporum and other non-dimorphic (plant) pathogenic fungi for parasitic growth.
Michielse
Caroline B
CB
Plant Pathology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands. c.b.michielse@uni-muenster.de
van Wijk
Ringo
R
Reijnen
Linda
L
Manders
Erik M M
EM
Boas
Sonja
S
Olivain
Chantal
C
Alabouvette
Claude
C
Rep
Martijn
M
D000595:Amino Acid Sequence; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005670:Fusarium / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000472:pathogenicity*; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal / Q000502:physiology; D006790:Host-Parasite Interactions / Q000235:genetics*; D018551:Solanum lycopersicum / Q000469:parasitology; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology; D030781:Organisms, Genetically Modified; D010802:Phylogeny; D018517:Plant Roots / Q000469:parasitology; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000235:genetics
D005656:Fungal Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors