Expression profiling and mutant analysis reveals complex regulatory networks involved in Arabidopsis response to Botrytis infection

Synan AbuQamar, Xi Chen, Rahul Dhawan, Burton Bluhm, John Salmeron, Stephen Lam, Robert A. Dietrich, Tesfaye Mengiste

Research output: Contribution to journalArticlepeer-review

215 Citations (Scopus)

Abstract

The expression profiles of Botrytis-inoculated Arabidopsis plants were studied to determine the nature of the defense transcriptome and to identify genes involved in host responses to the pathogen. Normally resistant Arabidopsis wild-type plants were compared with coi1, ein2, and nahG plants that are defective in various defense responses and/or show increased susceptibility to Botrytis. In wild-type plants, the expression of 621 genes representing approximately 0.48% of the Arabidopsis transcriptome was induced greater than or equal to twofold after infection. Of these 621 Botrytis-induced genes (BIGs), 462 were induced at or before 36 h post-inoculation, and may be involved in resistance to the pathogen. The expression of 181 BIGs was dependent on a functional COI1 gene required for jasmonate signaling, whereas the expression of 63 and 80 BIGs were dependent on ethylene (ET) signaling or salicylic acid accumulation, respectively, based on results from ein2 and nahG plants. BIGs encode diverse regulatory and structural proteins implicated in pathogen defense and abiotic and oxidative-stress responses. Thirty BIGs encode putative DNA-binding proteins that belong to ET response, zinc-finger, MYB, WRKY, and HD-ZIP family transcription-factor proteins. Fourteen BIGs were studied in detail to determine their role in resistance to Botrytis. T-DNA insertion alleles of ZFAR1 (At2G40140), the gene encoding a putative zinc-finger protein with ankyrin-repeat domains, showed increased local susceptibility to Botrytis and sensitivity to germination in the presence of abscisic acid (ABA), supporting the role of ABA in mediating responses to Botrytis infection. In addition, two independent T-DNA insertion alleles in the WRKY70 gene showed increased susceptibility to Botrytis. The transcriptional activation of genes involved in plant hormone signaling and synthesis, removal of reactive oxygen species, and defense and abiotic-stress responses, coupled with the susceptibility of the wrky70 and zfar1 mutants, highlights the complex genetic network underlying defense responses to Botrytis in Arabidopsis.

Original languageEnglish
Pages (from-to)28-44
Number of pages17
JournalPlant Journal
Volume48
Issue number1
DOIs
Publication statusPublished - Oct 2006
Externally publishedYes

Keywords

  • Arabidopsis thaliana
  • Botrytis cinerea
  • Botrytis-induced genes
  • Defense response
  • Expression profiling
  • WRKY transcription factor

ASJC Scopus subject areas

  • Genetics
  • Plant Science
  • Cell Biology

Fingerprint

Dive into the research topics of 'Expression profiling and mutant analysis reveals complex regulatory networks involved in Arabidopsis response to Botrytis infection'. Together they form a unique fingerprint.

Cite this