The team used cryo-electron microscopy to reveal the structures of toxins specific to insects and crustaceans (right) from the Black Widow (left). © Photo: nickybay.com; Figure: Gatsogiannis team |
Phobias are often irrational by nature – especially in the case of spiders, as these creatures are usually more afraid of humans than vice-versa. But: some species are a force to be reckoned with – for example, the Latrodectus spider, more commonly known as the Black Widow. It catches its prey by using venom – to be precise, latrotoxins (LaTXs), a subclass of neurotoxins, or nerve poisons. A bite from a Black Widow can be fatal for humans.
The exact structure of the nerve poison was previously unclear, but Prof. Christos Gatsogiannis from the Institute of Medical Physics and Biophysics at Münster University investigated the substance – not only because of its uniqueness, but also with a view to possible medical applications. Using cryo-EM, and in collaboration with Gatsogiannis’ former colleagues at the Max Planck Institute in Dortmund and with researchers at Jacobs University Bremen, the team of Münster researchers succeeded in explaining the first structure of a latrotoxin. The team’s findings have now been published in the Nature Communications journal.
Neurotoxins are probably known to many non-specialists – in the form of botox, which is often used in cosmetic surgery. The Black Widow’s poison, however, has anything but a “beautifying” effect: LaTX was developed by nature primarily in order to immobilize insects – or simply kill them straight off. In the process, the toxins dock onto specific receptors on the surface of nerve cells and cause neurotransmitters to be released, for example through a calcium channel. As a result of the constant inflow of calcium ions into the cell, transmitters are given off which lead to seizures.