Soricidin

Soricidin is a paralytic oligopeptide found in the venomous saliva of the northern short-tailed shrew (Blarina brevicauda);^[1] in the wild, shrews use it to paralyze their prey (typically insects).^[2] Its name is a reference to "Soricidae", the family to which shrews belong.^[3]

In addition to blocking transmission of nerve impulses^[4] by inhibiting sodium channels, soricidin also inhibits the TRPV6 calcium channel,^[5] which is over-expressed in many epithelial-cell cancers; as a result, soricidin is able to selectively induce apoptosis^[6] in breast, ovarian, and prostate cancer.^[7]

It is 54 amino acids long.^[1] It was first extracted and identified in 2000, as a result of basic research^[3] by Jack Stewart of Mount Allison University.^[8]