Has been described to inhibit nicotinic acetylcholine receptor (nAChR) alpha-7/CHRNA7 subunits and to bind acetylcholine binding protein (AChBP) (Kd=29.5 nM) (PubMed:21214917). Expressed by the venom gland. Directed evolution was applied to create MicTx3 mutants that inhibit IL-6R and trypsin (PubMed:21214917, PubMed:24308378). It does not bind to interleukin-6 receptor (IL-6R) (PubMed:21214917). It probably does not inhibit trypsin (Probable). Belongs to the snake three-finger toxin family. Short-chain subfamily.