ProTx-III, new selective Nav1.7 blocker
ProTx-III (µ-TRTX-Tp1a; belongs to NaSpTx family 1) has been isolated from the venom of the Peruvian green-velvet tarantula Thrixopelma pruriens at the University of Queensland (Australia). ProTx-III has been described to be a selective inhibitor of Nav1.7 with an IC50 value around 2 nM. The synthetic version of Tp1a produced by Smartox yields similar results in terms of Nav1.7 inhibition (see Figure 1). Queensland scientists have described that ProTx-III induces no significant changes in the voltage dependence of activation or steady-state inactivation of Nav1.7. ProTx-III also inhibits Nav1.1, Nav1.2 and Nav1.6 at nanomolar concentrations and does not affects Cav channels and nicotinic acetylcholine receptors. ProTx-III demonstrates analgesic propertiesin vivo when injected intraplantary in mice prior treatment with OD1, an activator of Nav1.7, which induces spontaneous pain.
Fig 1: effect of 5nM Smartox ProTx-III on hNav1.7 current studied by eliciting voltage steps from -60 to +40 mV at a holding potential of -90 mV.
二硫鍵：Cys2-Cys17, Cys9-Cys22, Cys16-Cys29
長度 (aa)： 33
外觀：White lyophilized solid
可溶性： Water or saline buffer, 5 mg/mL maximum (recommendation)
Counterion: TFA salts
CAS 號：not available