IAA8 Antibody

Target Protein Overview

IAA8 belongs to the Aux/IAA family of transcriptional repressors involved in plant growth regulation. It interacts with auxin receptors (TIR1/AFB) and auxin response factors (ARFs) to modulate lateral root formation . Unlike other Aux/IAAs, IAA8 exhibits dual nuclear-cytosolic localization .

Antibody Applications in Research

IAA8 antibodies have been critical for:

• Protein Localization: GFP-fusion studies confirmed IAA8's unique subcellular distribution .

• Interaction Analysis: Yeast two-hybrid and BiFC assays demonstrated auxin-dependent binding to TIR1 and ARFs .

• Post-Translational Modification Studies: Detection of phosphorylation by mitogen-activated protein kinases (MPKs) under heat stress .

• Degradation Assays: Monitoring ubiquitin-mediated proteolysis via immunoblotting .

Interaction Dynamics

Functional Insights

• Lateral Root Development: Overexpression delays auxin-responsive gene expression, reducing lateral root density .

• Heat Stress Response: Phosphorylation at Ser-119/123/124 by MPKs blocks auxin-induced degradation, impairing flower development .

• Transcriptional Repression: IAA8 binds auxin response elements (AuxREs) in promoters of bZIP28/60 genes .

Validation Data

• Western Blot: Detects ~22 kDa IAA8 protein in transgenic Arabidopsis lines (anti-Flag epitope) .

• Immunoprecipitation: Used to study ubiquitination patterns (e.g., polyubiquitin chains in MG132-treated plants) .

• Chromatin Immunoprecipitation (ChIP): Confirmed promoter binding at AuxREs .

Research Limitations and Future Directions

• Current antibodies lack isoform specificity due to high homology among Aux/IAA proteins .

• Phospho-specific antibodies for Ser-119/123/124 residues are under development to study stress-induced modifications .