A team led by Berkeley Lab faculty biochemist Daniel Minor has discovered how a protein produced by bullfrogs binds to and inhibits the action of saxitoxin, the deadly neurotoxin made by cyanobacteria and dinoflagellates that causes paralytic shellfish poisoning. The findings, published this week in Science Advances, could lead to the first-ever antidote for the compound, which blocks nerve signaling in animal muscles, causing death by asphyxiation when consumed in sufficient quantities.
The Kv7 family of voltage-gated potassium channels control excitability in the heart, brain, and ear, and harbor mutations associated with arrhythmias, epilepsy, and deafness. A recent study, led by Molecular Biophysics and Integrated Bioimaging (MBIB) faculty scientist Daniel Minor’s group in the Cardiovascular Research Institute at UCSF, used both diffraction and scattering beamlines of ALS-ENABLE to reveal a universal switch mechanism by which the calcium sensor protein calmodulin controls the action of these channels. The findings, reported in the journal Neuron, provide a key link between Kv7 channel activity and cellular signaling pathways. Greg Hura, a research scientist in MBIB, was also a co-author on the paper. Watch a video detailing the work.