• Bulletin of the Korean Chemical Society
• /
• v.33 no.9
• /
• pp.3091-3094
• /
• 2012

• BMB Reports
• /
• v.49 no.12
• /
• pp.693-698
• /
• 2016

In this study, a tissue-specific GAL4/UAS activation tagging system was used for the characterization of genes which could induce lethality when ubiquitously expressed. A dominant mutant exhibiting stunted growth was isolated and named defective root development 1-D (drd1-D). The T-DNA tag was located within the promoter region of AtTX12, which is predicted to encode a truncated nucleotide-binding leucine-rich repeat (NLR) protein, containing a Toll/interleukin-1 receptor (TIR) domain. The transcript levels of AtTX12 and defense-related genes were elevated in drd1-D, and the misexpression of AtTX12 recapitulated the drd1-D phenotypes. In the presence of ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1), a key transducer of signals triggered by TIR-type NLRs, a low-level of AtTX12 misexpression induced strong defective phenotypes including seedling lethality whereas, in the absence of EDS1, a high-level of AtTX12 misexpression induced weak growth defects like dwarfism, suggesting that AtTX12 might function mainly in an EDS1-dependent and partially in an EDS1-independent manner.

• Journal of Life Science
• /
• v.21 no.1
• /
• pp.36-43
• /
• 2011

Diabetes mellitus is associated with vascular complications. Diabetic patients exhibit high levels of glycated adducts in serum compared to non-diabetic individuals. The aim of this study was to investigate whether extracellular glycated albumin (GA) predisposes vascular smooth muscle cells (VSMCs) to pro-inflammatory phenotype. Exposure of rat aortic smooth muscle cells (AoSMCs) to GA not only enhanced interleukin-6 (IL-6) release but also activated promoter activity of the IL-6 gene. GA-induced IL-6 promoter activation was suppressed by dominant-negative forms of Toll-like receptor (TLR)-4 and myeloid differentiation factor 88 (MyD88), but not by dominant-negative-forms of TLR-2 and TIR-domain-containing adapter-inducing interferon-$\beta$ (TRIF). Extracellular signal-regulated kinase (ERK) inhibition and diphenyleneiodium (DPI) also attenuated IL-6 induction by GA. Mutation at the nuclear factor-${\kappa}B$ (NF-${\kappa}B$)-binding site in the IL-6 promoter region suppressed promoter activation in response to GA. The present study proposes that GA would contribute to inflammatory reaction in the stressed vasculature by inducing IL-6 in VSMCs, and that TLR-4, EKR, and NF-${\kappa}B$ play active roles in the process.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.1
• /
• pp.130-137
• /
• 2007

A disease resistance related gene, MbR7, was identified in the wild apple species, Malus baccata. The MbR7 gene has a single open reading frame (ORF) of 3,288 nucleotides potentially encoding a 1,095-amino acid protein. Its deduced amino acid sequence resembles the N protein of tobacco and the NL27 gene of potato and has several motifs characteristic of a TIR-NBS-LRR R gene subclass. Ectopic expression of MbR7 in Arabidopsis enhanced the resistance against a virulent pathogen, Pseudomonas syringae pv. tomato DC3000. Microarray analysis confirmed the induction of defense-related gene expression in 35S::MbR7 heterologous Arabidopsis plants, indicating that the MbR7 gene likely activates a downstream resistance pathway without interaction with pathogens. Our results suggest that MbR7 can be a potential target gene in developing a new disease-resistant apple variety.

• Journal of Life Science
• /
• v.18 no.12
• /
• pp.1637-1643
• /
• 2008

This study has investigated whether extracellular HSP90 predisposes vascular smooth muscle cells (VSMCs) to pro-inflammatory phenotype. Exposure of rat aortic smooth muscle cells to HSP90 not only enhanced IL-6 release but also profoundly induced IL-6 transcript via promoter activation. HSP90-induced IL-6 promoter activation was suppressed by dominant-negative forms of Toll-like receptor (TLR)-4 and myeloid differentiation factor 88 (MyD88), but not by dominant-negative-forms of TLR-3 and TIR-domain-containing adapter-inducing interferon-${\beta}$ (TRIF). Curcumin, which inhibits dimerization of TLR-4, also attenuated the IL-6 induction by HSP90. Mutation at the NF-${\kappa}B$- or C/EBP-binding site in the IL-6 promoter region suppressed the promoter activation in response to HSP90. The gene delivery of $I{\kappa}B$ using recombinant adenoviruses and treatment with resveratrol, which inhibit NF-${\kappa}B$ activity, attenuated the HSP90-induced IL-6 release from VSMCs. The present study proposes that extracellular HSP90 would contribute to inflammatory reaction in the stressed vasculature by inducing IL-6 in VSMCs, and that TLR-4 and NF-${\kappa}B$ would play active roles in the process.