The glyoxylate cycle is required for temporal regulation of virulence by the plant pathogenic fungus Magnaporthe grisea.
We describe the isolation and characterization of ICL1 from the rice blast fungus Magnaporthe grisea, a gene that encodes isocitrate lyase, one of the principal enzymes of the glyoxylate cycle. ICL1 shows elevated expression during development of infection structures and cuticle penetration, and a targeted gene replacement showed that the gene is required for full virulence by M. grisea. In particular, we found that the prepenetration stage of development, before entry into plant tissue, is affected by loss of the glyoxylate cycle. There is a delay in germination, infection-related development and cuticle penetration in Delta icl1 mutants. Recent reports have shown the importance of the glyoxylate cycle in the virulence of the human pathogenic fungus Candida albicans and the bacterial pathogen Mycobacterium tuberculosis. Our results indicate that the glyoxylate cycle is also important in this plant pathogenic fungus, demonstrating the widespread utility of the pathway in microbial pathogenesis.
Wang
Zheng-Yi
ZY
School of Biological Sciences, University of Exeter, Washington Singer Laboratories, Exeter EX4 4QG, UK.
Thornton
Christopher R
CR
Kershaw
Michael J
MJ
Debao
Li
L
Talbot
Nicholas J
NJ
D000595:Amino Acid Sequence; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D018390:Gene Targeting / Q000379:methods; D006038:Glyoxylates / Q000378:metabolism*; D007522:Isocitrate Lyase / Q000235:genetics / Q000378:metabolism*; D020082:Magnaporthe / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity*; D008969:Molecular Sequence Data; D009154:Mutation; D030781:Organisms, Genetically Modified; D010935:Plant Diseases / Q000382:microbiology; D010944:Plants / Q000382:microbiology; D017386:Sequence Homology, Amino Acid; D014774:Virulence / Q000502:physiology
D005656:Fungal Proteins; D006038:Glyoxylates; D007522:Isocitrate Lyase; C031150:glyoxylic acid