| 摘 要： | Conotoxins belong to the large families of disulfide-rich peptide toxins from cone snail venom, and can act on a broad spectrum of ion channels and receptors. They are classified into different subtypes based on their targets. The α-conotoxins selectively inhibit the current of the nicotinic acetylcholine receptors. Because of their unique selectivity towards distinct n ACh R subtypes, α-conotoxins become valuable tools in n ACh R study. In addition to the X-ray structures of α-conotoxins in complex with acetylcholine-binding protein, a homolog of the n ACh R ligand-binding domain, the high-resolution crystal structures of the extracellular domain of the α1 and α9 subunits are also obtained. Such structures not only revealed the details of the configuration of n ACh R, but also provided higher sequence identity templates for modeling the binding modes of α-conotoxins to n ACh R. This mini-review summarizes recent modeling studies for the determination of the binding modes of α-conotoxins to n ACh R. As there are not crystal structures of the n ACh R in complex with conotoxins, computational modeling in combination of mutagenesis data is expected to reveal the molecular recognition mechanisms that govern the interactions between α-conotoxins and n ACh R at molecular level. An accurate determination of the binding modes of α-conotoxins on ACh Rs allows rational design of α-conotoxin analogues with improved potency or selectivity to n ACh Rs.
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