Skip to main content
PMC home page
Plant Physiology logoLink to Plant Physiology
. 1993 Sep;103(1):91–96. doi: 10.1104/pp.103.1.91

The AVR9 race-specific elicitor of Cladosporium fulvum is processed by endogenous and plant proteases.

G F Van den Ackerveken 1, P Vossen 1, P J De Wit 1
PMCID: PMC158950  PMID: 8208859

Abstract

The avirulence gene avr9 of the fungal tomato pathogen Cladosporium fulvum encodes a race-specific peptide elicitor that induces a hypersensitive response in tomato plants carrying the complementary resistance gene Cf9. The avr9 gene is highly expressed when C. fulvum is growing in the plant and the elicitor accumulates in infected leaves as a 28-amino acid (aa) peptide. In C. fulvum grown in vitro, the peptide elicitor is not produced in detectable amounts. To produce significant amounts of the AVR9 elicitor in vitro, the coding and termination sequences of the avr9 gene were fused to the constitutive gpd-promoter (glyceraldehyde 3-phosphate dehydrogenase) of Aspergillus nidulans. Transformants of C. fulvum were obtained that highly expressed the avr9 gene in vitro and produced active AVR9 peptide elicitors. These peptides were partially sequenced from the N terminus and appeared to consist of 32, 33, and 34 aa's, respectively, and are the precursors of the mature 28-aa AVR9 peptide. We demonstrated that plant factors process the 34-aa peptide into the mature 28-aa peptide. We present a model for the processing of AVR9 involving cleavage of a signal peptide during excretion and further maturation by fungal and plant proteases into the stable 28-aa peptide elicitor.

Full Text

The Full Text of this article is available as a PDF (1.8 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Ahern T. J., Klibanov A. M. The mechanisms of irreversible enzyme inactivation at 100C. Science. 1985 Jun 14;228(4705):1280–1284. doi: 10.1126/science.4001942. [DOI] [PubMed] [Google Scholar]
  2. Cervone F., Hahn M. G., De Lorenzo G., Darvill A., Albersheim P. Host-Pathogen Interactions : XXXIII. A Plant Protein Converts a Fungal Pathogenesis Factor into an Elicitor of Plant Defense Responses. Plant Physiol. 1989 Jun;90(2):542–548. doi: 10.1104/pp.90.2.542. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. De Wit P. J., Hofman A. E., Velthuis G. C., Kuć J. A. Isolation and Characterization of an Elicitor of Necrosis Isolated from Intercellular Fluids of Compatible Interactions of Cladosporium fulvum (Syn. Fulvia fulva) and Tomato. Plant Physiol. 1985 Mar;77(3):642–647. doi: 10.1104/pp.77.3.642. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Punt P. J., Dingemanse M. A., Jacobs-Meijsing B. J., Pouwels P. H., van den Hondel C. A. Isolation and characterization of the glyceraldehyde-3-phosphate dehydrogenase gene of Aspergillus nidulans. Gene. 1988 Sep 15;69(1):49–57. doi: 10.1016/0378-1119(88)90377-0. [DOI] [PubMed] [Google Scholar]
  5. Punt P. J., Oliver R. P., Dingemanse M. A., Pouwels P. H., van den Hondel C. A. Transformation of Aspergillus based on the hygromycin B resistance marker from Escherichia coli. Gene. 1987;56(1):117–124. doi: 10.1016/0378-1119(87)90164-8. [DOI] [PubMed] [Google Scholar]
  6. Roberts I. N., Oliver R. P., Punt P. J., van den Hondel C. A. Expression of the Escherichia coli beta-glucuronidase gene in industrial and phytopathogenic filamentous fungi. Curr Genet. 1989 Mar;15(3):177–180. doi: 10.1007/BF00435503. [DOI] [PubMed] [Google Scholar]
  7. Rodrigo I., Vera P., Conejero V. Degradation of tomato pathogenesis-related proteins by an endogenous 37-kDa aspartyl endoproteinase. Eur J Biochem. 1989 Oct 1;184(3):663–669. doi: 10.1111/j.1432-1033.1989.tb15064.x. [DOI] [PubMed] [Google Scholar]
  8. Schägger H., von Jagow G. Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the separation of proteins in the range from 1 to 100 kDa. Anal Biochem. 1987 Nov 1;166(2):368–379. doi: 10.1016/0003-2697(87)90587-2. [DOI] [PubMed] [Google Scholar]
  9. Steck G., Leuthard P., Bürk R. R. Detection of basic proteins and low molecular weight peptides in polyacrylamide gels by formaldehyde fixation. Anal Biochem. 1980 Sep 1;107(1):21–24. doi: 10.1016/0003-2697(80)90486-8. [DOI] [PubMed] [Google Scholar]
  10. Van den Ackerveken G. F., Van Kan J. A., De Wit P. J. Molecular analysis of the avirulence gene avr9 of the fungal tomato pathogen Cladosporium fulvum fully supports the gene-for-gene hypothesis. Plant J. 1992 May;2(3):359–366. doi: 10.1111/j.1365-313x.1992.00359.x. [DOI] [PubMed] [Google Scholar]
  11. Vera P., Conejero V. Pathogenesis-related proteins of tomato : p-69 as an alkaline endoproteinase. Plant Physiol. 1988 May;87(1):58–63. doi: 10.1104/pp.87.1.58. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. van Kan J. A., van den Ackerveken G. F., de Wit P. J. Cloning and characterization of cDNA of avirulence gene avr9 of the fungal pathogen Cladosporium fulvum, causal agent of tomato leaf mold. Mol Plant Microbe Interact. 1991 Jan-Feb;4(1):52–59. doi: 10.1094/mpmi-4-052. [DOI] [PubMed] [Google Scholar]
  13. von Heijne G. A new method for predicting signal sequence cleavage sites. Nucleic Acids Res. 1986 Jun 11;14(11):4683–4690. doi: 10.1093/nar/14.11.4683. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Plant Physiology are provided here courtesy of Oxford University Press

RESOURCES