FVKILRYENEVLQLEEDEDF (βadp1). This 20-amino-acid peptide maps to the Ig-like extracellular domain of the voltage-gated sodium channel β1 subunit (SCN1B). It is specifically located within residues 1–20 of the Ig loop and has been named βadp1. Structural modeling and docking studies demonstrate that βadp1 binds to the adhesion interface of the β1 Ig domain, functioning as a competitive inhibitor of β1-mediated intercellular adhesion.
Functional & Experimental Applications
- Inhibition of Intercellular Adhesion:
βadp1 significantly and dose-dependently reduces junctional electrical resistance in cell monolayers overexpressing the sodium channel β1 subunit, but has no effect in parental cells lacking β1.
- Implications for Cardiac Electrophysiology:
β1-mediated adhesion at the perinexus—the region adjacent to gap junctions—is critical for action potential propagation between cardiomyocytes. By interfering with this adhesion, βadp1 provides insight into novel targets for anti-arrhythmic strategies
βadp1 (FVKILRYENEVLQLEEDEDF) is a thoughtfully designed peptide derived from the cell adhesion domain of the sodium channel β1 subunit. By inhibiting β1-mediated junctional adhesion, it serves as a powerful tool to dissect mechanisms of electrical coupling in cardiomyocytes and holds promise as a molecular probe for exploring arrhythmia-targeted therapies. | 