Overexpression of the TIR-X gene results in a dwarf phenotype and activation of defense-related gene expression in Arabidopsis thaliana

Hiroaki Kato; Tamao Saito; Hidetaka Ito; Yoshibumi Komeda; Atsushi Kato

doi:10.1016/j.jplph.2013.12.002

Overexpression of the TIR-X gene results in a dwarf phenotype and activation of defense-related gene expression in Arabidopsis thaliana

J Plant Physiol. 2014 Mar 15;171(6):382-8. doi: 10.1016/j.jplph.2013.12.002. Epub 2014 Feb 14.

Authors

Hiroaki Kato¹, Tamao Saito², Hidetaka Ito³, Yoshibumi Komeda⁴, Atsushi Kato⁵

Affiliations

¹ Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Sapporo 060-0810, Japan.
² Department of Materials and Life Sciences, Faculty of Science and Technology, Sophia University, Chiyoda-ku, Tokyo 120-8554, Japan.
³ Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan; Japan Science and Technology Agency, PRESTO, Kawaguchi, Saitama 332-0012, Japan.
⁴ Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo, Tokyo 113-0033, Japan.
⁵ Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan. Electronic address: atsushi@sci.hokudai.ac.jp.

PMID: 24594389
DOI: 10.1016/j.jplph.2013.12.002

Abstract

The Arabidopsis genome encodes various proteins with a Toll/interleukin-1 receptor (TIR) domain. Many of these proteins also contain nucleotide-binding site (NBS) and leucine-rich repeat (LRR) domains and function as resistance (R) proteins. However, the protein encoded by At2g32140 (a TIR-X gene) contains a TIR domain but lacks NBS and LRR domains. We found that transgenic plants overexpressing At2g32140 displayed a dwarf phenotype and showed increased expression of defense-related genes. In general, the growth defect caused by activation of defense responses is suppressed under high-temperature conditions. However, transgenic plants overexpressing At2g32140 displayed a much stronger dwarf phenotype at 28°C than at 22°C. This dwarf phenotype was suppressed under the combination with known salicylic-acid pathway mutants. These findings suggest that At2g32140 encodes a protein involved in the plant defense response.

Keywords: Arabidopsis thaliana; Dwarf phenotype; R-Gene; Salicylic acid; TIR domain.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Amino Acid Sequence
Arabidopsis / genetics*
Arabidopsis / growth & development
Arabidopsis / immunology
Arabidopsis / physiology
Arabidopsis Proteins / genetics*
Arabidopsis Proteins / metabolism
Binding Sites
Flowers / genetics
Flowers / growth & development
Flowers / immunology
Flowers / physiology
Gene Expression
Gene Expression Regulation, Plant*
Molecular Sequence Data
Mutation
Phenotype
Plant Diseases / immunology*
Plant Immunity / genetics*
Plant Leaves / genetics
Plant Leaves / growth & development
Plant Leaves / immunology
Plant Leaves / physiology
Plants, Genetically Modified
Protein Structure, Tertiary
Receptors, Cell Surface / genetics*
Receptors, Cell Surface / metabolism
Salicylic Acid / metabolism
Sequence Alignment
Signal Transduction
Temperature

Substances

Arabidopsis Proteins
At2g32140 protein, Aeabidopsis
Receptors, Cell Surface
Salicylic Acid