Grasshopper mice aren’t just cute: they EAT scorpions. The painful, potentially deadly stings of ark scorpions don’t bother them; stings are just par for the course in devouring a meal.
In a paper published in Science, MSU BEACONite Ashlee Rowe and colleagues demonstrated that the grasshopper mice are essentially numb to the pain caused by the toxin in the sting.
By sequencing the genes for the different sodium channels which respond to the toxin, the scientists discovered that one channel in the grasshopper mice has amino acids different from other mammals sensitive to bark scorpion stings.
By binding to this particular sodium channel in the mouse pain neurons, the toxin blocks the firing of a pain signal to the brain. Thus, the toxin acts as an analgesic rather than a pain stimulant, leaving the mice generally resistant to the bark scorpion toxin.
“We know the region of the channel where this is taking place and the amino acids involved,” she said. “But there’s something else that’s playing a role, and that’s what I’m focusing on next.”
[Written as part of my work with the BEACON Buzz]