Identification and characterization of suppressor mutants of spl11- mediated cell death in rice

Mol Plant Microbe Interact. 2014 Jun;27(6):528-36. doi: 10.1094/MPMI-08-13-0259-R.

Abstract

Lesion mimic mutants have been used to dissect programmed cell death (PCD) and defense-related pathways in plants. The rice lesion-mimic mutant spl11 exhibits race nonspecific resistance to the bacterial pathogen Xanthomonas oryzae pv. oryzae and the fungal pathogen Magnaporthe oryzae. Spl11 encodes an E3 ubiquitin ligase and is a negative regulator of PCD in rice. To study the regulation of Spl11-mediated PCD, we performed a genetic screen and identified three spl11 cell-death suppressor (sds) mutants. These suppressors were characterized for their resistance to X. oryzae pv. oryzae and M. oryzae and for their expression of defense-related genes. The suppression of the cell-death phenotypes was generally correlated with reduced expression of defense-related genes. When rice was challenged with avirulent isolates of M. oryzae, the disease phenotype was unaffected in the sds mutants, indicating that the suppression might be Spl11-mediated pathway specific and may only be involved in basal defense. In addition, we mapped one of the suppressor mutations to a 140-kb interval on the long arm of rice chromosome 1. Identification and characterization of these sds mutants should facilitate our efforts to elucidate the Spl11-mediated PCD pathway.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cell Death
  • Chromosome Mapping
  • Gene Expression Regulation, Plant*
  • Magnaporthe / pathogenicity*
  • Mutation
  • Oryza / genetics*
  • Oryza / immunology
  • Oryza / physiology
  • Phenotype
  • Plant Diseases / immunology*
  • Plant Diseases / microbiology
  • Plant Immunity*
  • Plant Leaves / genetics
  • Plant Leaves / immunology
  • Plant Leaves / physiology
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / metabolism
  • Xanthomonas / pathogenicity*

Substances

  • Plant Proteins
  • Ubiquitin-Protein Ligases