[3] CRISPs are also found in a variety of snake venoms where they inhibit both smooth muscle contraction and cyclic nucleotide-gated ion channels.

[1] CRISPs are glycoproteins, with a number of carbohydrate glycans covalently attached to amino acid side-chains on their surface via glycosylation.

[2] Given the involvement of CRISPs in several stages of human reproduction, it is unsurprising that applications in treatment of infertility and as contraceptives are being actively investigated.

These venoms are toxic due to their blocking of calcium channels and also because they reduce potassium-induced smooth muscle contraction.

The selective ion channel activity of snake CRISPs, coupled with the variety of CRISPs available as the pool of venom proteins appears highly variable between (at least) cobra species, provide a valuable tool for probing the mechanisms of ion channel activity.