Nanomechanical unfolding of α-neurexin: A major component of the synaptic junction

• Published in: Chemical physics letters 2012-01, Vol.521, p.134-137
• Main Authors: Mikulska, K., Strzelecki, J., Balter, A., Nowak, W.
• Format: Article
• Language: English
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2011.11.033

[Display omitted] ► Synapse protein rat neurexin 1α has been studied by AFM for the first time. ► Single molecule force spectra indicate a flexible hinge between L5 and E3 domains. ► LNS/LG domains unfold under a uniform force of 100pN. ► Double maxima in AFM spectra suggest existence of intermediates. ► Nanomechanical data help to understand better neuron synapses. Neurexins are proteins involved in synapse signaling. Understanding molecular recognition in neurons requires a knowledge of neurexin elasticity at a single molecule level. We apply, for the first time, AFM force spectroscopy to reveal mechanical properties of rat neurexin 1α (NRXN1α). Spectra indicate a flexible hinge. The first event in the unfolding pathway is a change of neurexin shape accompanied by EGF-like E3 domain unfolding. This requires low forces on the order of 50pN. The other LNS/LG domains require forces of 100pN to be unfolded. The unfolding of core modules (L1–E1–L2) and (L3–E2–L4) is a two stage process.