Your friend the tarantula

Gregory Nemec

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One day, you might not get Novocaine before you have a tooth drilled. You might get a shot derived from tarantula venom instead.

Or, to be more precise, you might get a shot of a protein that Yale researchers have identified in the venom of the Peruvian green velvet tarantula. This protein has the potential to blunt activity in pain-transmitting neurons. The researchers found it through a process they call “toxineering”: use of a screening platform that allowed them to analyze toxins from a host of tarantula species. The one they singled out blocks TRPA1, an ion channel on the surface of pain-sensing neurons. (Ion channels are specialized proteins embedded in the surface of all cells. By regulating the flow of specific ions in and out of the cells, they mediate electrical signaling in neurons.) 

The researchers tested the spider toxins on only one of a dozen suspected human pain channels, but they hope the new screening method will let them search millions of spider toxins for safe, pain-killing drugs.  The findings were published in the journal Current Biology.

The idea of a painkiller in tarantula venom sounds surprising, “because tarantulas are horrible—and deadly,” says senior author Michael Nitabach, a Yale associate professor of cellular and molecular physiology and genetics. But the two neuropathic responses—the deadly and the soothing—are connected. The toxins in venom relieve pain because they block or activate ion channels, and the reason they block or activate ion channels is to disrupt electrical function and cause paralysis in a spider’s prey.

Spider venom won’t work on all pain, Nitabach says, but for certain forms of peripheral pain, such as postoperative wound pain, “it’s very possible.”