SABP2: A Potential MeSA Receptor Mediating Aphid Resistance in Plants

As a salicylic acid (SA)-binding protein, SABP2 has been shown to play a crucial role in plant defense mechanisms. This study reveals that SABP2 can also bind to methyl salicylate (MeSA) and is essential for converting intracellular MeSA into SA. This finding suggests that SABP2 may function as an odorant-binding protein (OBP)-like receptor, perceiving volatile MeSA signals emitted from plants under stress and converting them into SA. This process is proposed to trigger NAC2-mediated aphid resistance.

To investigate this hypothesis, the researchers first confirmed the binding affinity of SABP2 to SA. Subsequently, they conducted competitive binding assays to determine whether MeSA could influence the specific SA-binding activity of SABP2. The results provide evidence for the potential role of SABP2 as a key receptor in mediating plant defense responses against aphids.

This discovery sheds light on the intricate mechanisms by which plants perceive and respond to environmental threats. Further research on SABP2's interaction with MeSA and SA, and its specific role in aphid resistance, could contribute to developing novel pest control strategies and enhancing plant protection.