At1g61340 Antibody

Gene and Protein Overview

The AT1G61340 gene encodes FBS1 (F-box Stress Induced 1), an F-box domain-containing protein induced by biotic and abiotic stressors . Key details include:

Role in Stress Responses

FBS1 interacts with WD40 repeat-like proteins (FBIP1 and FBIP2) to regulate stress-responsive genes. This interaction is mediated by the N-terminal domain of FBS1, which contains an LXLXL motif (a variant of the EAR repressor motif) . Key findings include:

• Biotic Stress: FBS1 modulates defense priming and systemic acquired resistance (SAR) against pathogens like Pseudomonas .

• Abiotic Stress: Regulates genes responsive to salinity, drought, and nutrient deficiencies (e.g., nitrate/phosphate signaling) .

Transcriptional Regulation

FBS1 collaborates with GARP transcription factors (e.g., NIGT1.1) to repress or activate stress-related genes. For example:

• Nitrogen/Phosphate Signaling: FBS1 interacts with NIGT1.1 to integrate nutrient cues in roots .

• Abscisic Acid (ABA) Signaling: FBS1 influences ABA-responsive genes, linking stress perception to hormonal regulation .

Protein Degradation Pathways

FBS1 may function in ubiquitination-mediated protein degradation. While direct evidence is limited, its F-box domain suggests involvement in SCF (Skp1-Cullin-F-box) E3 ligase complexes . This mechanism could regulate stability of stress-responsive transcription factors.

Interaction Partners

FBS1 interacts with:

1. FBIP1/FBIP2: WD40 repeat proteins that scaffold transcriptional regulators .

2. 14-3-3 Proteins: Phosphorylation-dependent regulators of stress responses .

3. NIGT1.1: A GARP transcription factor involved in nitrate/phosphate signaling .

Experimental Evidence

• Yeast Two-Hybrid Assays: Confirmed FBS1-FBIP1 interaction via N-terminal domain (residues 1–80) .

• Western Blotting: Used to detect FBS1 in plant tissues under stress conditions (e.g., salt, pathogen exposure) .

• Gene Expression Profiling: FBS1 mutants show altered expression of defense-related genes (e.g., PR1, PDF1.2) .

Table 2: Functional Insights from FBS1 Research