Format

Send to

Choose Destination
Plant Physiol. 2010 Dec;154(4):1766-82. doi: 10.1104/pp.110.163915. Epub 2010 Oct 4.

The Arabidopsis Botrytis Susceptible1 Interactor defines a subclass of RING E3 ligases that regulate pathogen and stress responses.

Author information

1
Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907-2054, USA.

Abstract

We studied the function of Arabidopsis (Arabidopsis thaliana) Botrytis Susceptible1 Interactor (BOI) in plant responses to pathogen infection and abiotic stress. BOI physically interacts with and ubiquitinates Arabidopsis BOS1, an R2R3MYB transcription factor previously implicated in stress and pathogen responses. In transgenic plants expressing the BOS1-β-glucuronidase transgene, β-glucuronidase activity could be detected only after inhibition of the proteosome, suggesting that BOS1 is a target of ubiquitin-mediated degradation by the proteosome. Plants with reduced BOI transcript levels generated through RNA interference (BOI RNAi) were more susceptible to the necrotrophic fungus Botrytis cinerea and less tolerant to salt stress. In addition, BOI RNAi plants exhibited increased cell death induced by the phytotoxin α-picolinic acid and by a virulent strain of the bacterial pathogen Pseudomonas syringae, coincident with peak disease symptoms. However, the hypersensitive cell death associated with different race-specific resistance genes was unaffected by changes in the level of BOI transcript. BOI expression was enhanced by B. cinerea and salt stress but repressed by the plant hormone gibberellin, indicating a complex regulation of BOI gene expression. Interestingly, BOI RNAi plants exhibit reduced growth responsiveness to gibberellin. We also present data revealing the function of three Arabidopsis BOI-RELATED GENES (BRGs), which contribute to B. cinerea resistance and the suppression of disease-associated cell death. In sum, BOI and BRGs represent a subclass of RING E3 ligases that contribute to plant disease resistance and abiotic stress tolerance through the suppression of pathogen-induced as well as stress-induced cell death.

PMID:
20921156
PMCID:
PMC2996010
DOI:
10.1104/pp.110.163915
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center