2019 - Development of Photocrosslinking Probes Based on Huwentoxin-IV to Map the Site of Interaction on Nav1.7
SyncroPatch 768PE (a predecessor model of the SyncroPatch 384/768i) Publication in Cell Chemical Biology (2019)
Tzakoniati F., Xu H., Li T., Garcia N., Kugel C., Payandeh J., Koth C.M., Tate E.W.
Cell Chemical Biology (2019) In Press, corrected proof doi.org/10.1016/j.chembiol.2019.10.011
- Development of six potent diazirine-containing photoprobes based on Huwentoxin-IV
- Photoprobes specifically photolabel purified bacterial-Nav1.7 VSD2 chimeric channels
- Proteomic mass spectrometry identifies binding site on S1-S2 loop and S3 helix
- Proposed model of HwTx-IV binding reveals importance of K27 and R29
Voltage-gated sodium (Nav) channels respond to changes in the membrane potential of excitable cells through the concerted action of four voltage-sensor domains (VSDs). Subtype Nav1.7 plays an important role in the propagation of signals in pain-sensing neurons and is a target for the clinical development of novel analgesics. Certain inhibitory cystine knot (ICK) peptides produced by venomous animals potently modulate Nav1.7; however, the molecular mechanisms underlying their selective binding and activity remain elusive. This study reports on the design of a library of photoprobes based on the potent spider toxin Huwentoxin-IV and the determination of the toxin binding interface on VSD2 of Nav1.7 through a photocrosslinking and tandem mass spectrometry approach. Our Huwentoxin-IV probes selectively crosslink to extracellular loop S1-S2 and helix S3 of VSD2 in a chimeric channel system. Our results provide a strategy that will enable mapping of sites of interaction of other ICK peptides on Nav channels.