SIZ1 small ubiquitin-like modifier E3 ligase facilitates basal thermotolerance in Arabidopsis independent of salicylic acid.

Abstract

Small ubiquitin-like modifier (SUMO) conjugation/deconjugation to heat shock transcription factors regulates DNA binding of the peptides and activation of heat shock protein gene expression that modulates thermal adaptation in metazoans. SIZ1 is a SUMO E3 ligase that facilitates SUMO conjugation to substrate target proteins (sumoylation) in Arabidopsis (Arabidopsis thaliana). siz1 T-DNA insertional mutations (siz1-2 and siz1-3; Miura et al., 2005) cause basal, but not acquired, thermosensitivity that occurs in conjunction with hyperaccumulation of salicylic acid (SA). NahG encodes a salicylate hydroxylase, and expression in siz1-2 seedlings reduces endogenous SA accumulation to that of wild-type levels and further increases thermosensitivity. High temperature induces SUMO1/2 conjugation to peptides in wild type but to a substantially lesser degree in siz1 mutants. However, heat shock-induced expression of genes, including heat shock proteins, ascorbate peroxidase 1 and 2, is similar in siz1 and wild-type seedlings. Together, these results indicate that SIZ1 and, by inference, sumoylation facilitate basal thermotolerance through processes that are SA independent.

• Authors: Chan Yul Yoo, Kenji Miura, Jing Bo Jin, Jiyoung Lee, Hyeong Cheol Park, David E Salt, Dae-Jin Yun, Ray A Bressan, Paul M Hasegawa
• Journal: Plant physiology (Plant Physiol) Vol. 142 Issue 4 Pg. 1548-58 (Dec 2006) ISSN: 0032-0889 [Print] United States
• PMID: 17041025 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Arabidopsis Proteins
• DNA-Binding Proteins
• Heat Shock Transcription Factors
• Heat-Shock Proteins
• Small Ubiquitin-Related Modifier Proteins
• Transcription Factors
• Ubiquitin-Protein Ligases
• Ligases
• SIZ1 protein, Arabidopsis
• Salicylic Acid

Topics

• Arabidopsis (drug effects, metabolism, physiology)
• Arabidopsis Proteins (genetics, metabolism, physiology)
• DNA-Binding Proteins (genetics, metabolism)
• Gene Expression Regulation, Plant
• Heat Shock Transcription Factors
• Heat-Shock Proteins (metabolism)
• Ligases (genetics, metabolism, physiology)
• Mutation
• Regulon (physiology)
• Salicylic Acid (metabolism)
• Small Ubiquitin-Related Modifier Proteins (genetics, metabolism, physiology)
• Temperature
• Transcription Factors (genetics, metabolism)
• Ubiquitin-Protein Ligases (genetics, metabolism, physiology)