Terahertz waves promote Ca2+ transport in the Cav2.1 channel.

CaV2.1 channels are the structural foundation for neurotransmitter transmission and other vital biological processes. If autoimmune-mediated reduction in presynaptic CaV2.1 leads to a decrease in calcium influx during a presynaptic action potential, which decreases chemical neurotransmission, leading to a debilitating neuromuscular weakness, also known as Lambert-Eaton myasthenia syndrome. The selectivity filter is a core structural component of CaV2.1 channels, with a pivotal role in regulating the selective permeation of Ca2+ ions. Due to the vibration and rotation frequencies of the selectivity filter of CaV2.1 being located in the terahertz band, terahertz waves at specific frequencies may resonate with it, thereby affecting Ca2+ current passing through CaV2.1. Therefore, it is highly worthwhile to study how the terahertz waves regulate the CaV2.1 channel. In this study, we investigate the structure of CaV2.1 channels using molecular dynamics simulations. The effect of external terahertz waves on the channel has been examined at different resonant frequencies of the selectivity filter. We found that when the frequency of terahertz waves applied is around the symmetrical vibration frequency of the carboxyl group in the selectivity filter, the PMF of CaV2.1 significantly decreases, promoting the transport of Ca2+ ions through CaV2.1. The reason behind this is that the terahertz waves resonate with the carboxyl groups of the selectivity filter, affecting the hydrogen network between the hydrated water of Ca2+ ions and the selectivity filter. These findings open up new treatment avenues for channel diseases such as Lambert-Eaton myasthenic syndrome treated with terahertz waves.