...evolution of venom-targeted nicotinic acetylcholine receptors in mammals that survive venomous snake bites.
Here is a link to the publication if you have access: Toxicon Volume 99, 1 June 2015, Pages 68–72
It appears that the Nicotinic Acetylcholine Receptor (nAChR) a protein, has two polymorphisms. From the text:
Our results extend the known cases of convergent evolution at venom-targeted nAChR receptors to include the honey badger and domestic pig. The honey badger and pig lineages independently acquired replacements that are biochemically similar to those seen in the hedgehog: W187R (all three species) and F189L, (L in honey badger and pig; I in hedgehog). In mongoose, substitutions at these same sites also occur, but they eliminate ?-neurotoxin binding through steric hindrance via glycosylation rather than charge interference via introduction of a positively charged amino acid. Hence, evolution of resistance in venom-targeted nAChR receptors shows that convergence in function at the same sites can be mediated through distinct biophysical mechanisms.
W187R means that that tryptophan at position 187 in the protein sequence is substituted with arginine in the honey badger and domestic pig, and that in position 189, phenylalanine is substituted with leucine in the honey badger and pig, and isoleucine in the hedgehog.
The central dogma of biology whereby the protein sequence corresponds to a genetic mutation is also discussed in the paper.
I hope the reader will find this interesting.
= new reply since forum marked as read
