The deadly strategy of the black widow spider; A flood of calcium in the synapses

Using state-of-the-art technologies, Professors Christos Gatsugiannis and Andreas Heuer created a 3D model of a process in motion to understand what happens to the neurotoxin once it enters the body.

High performance cryo-electron microscopy (cryo-EM) allowed them to study the structure of cells, according to Techna Technology Media Science News Department. Molecular dynamics (MD) simulations analyze the physical motions of atoms and molecules. With these tools, they were able to see how this moving neurotoxin works with powerful and vicious effects in 3D. They may know what α-latrotoxin does, but they don’t know how it works inside the body. When α-latrotoxin enters the bloodstream, it “disrupts the transmission of signals in the nervous system.” This toxin undergoes a surprising transformation when it binds to the receptor.

This poison affects the transmission of signals in the nervous system. As soon as α-latrotoxin binds to specific receptors at synapses—the connections between nerve cells or between nerve cells and muscles—calcium ions flood uncontrollably into the presynaptic membrane of the signaling cells. This causes the release of neurotransmitters and stimulates strong muscle contractions and spasms.

Now, scientists have understood the structure of this neurotoxin after reaching “near-atomic resolution.” They zoomed in on the “calcium entry” and discovered something unique. This toxin is transformed when it binds to a receptor. The toxic membrane “forms a stalk that penetrates the cell membrane like a syringe.” Amazingly, the toxin even “forms a tiny hole in the membrane that acts as a calcium channel,” which would kill the system.