Terahertz-induced conformational dynamics of synaptotagmin III

Synaptotagmin regulates neurotransmitter release by sensing changes in Ca²⁺ concentration, playing a crucial regulatory role in nerves, muscles, and various other systems. Terahertz (THz) waves, a safe and efficient new tool, have been widely used in biomedicine in recent years, but the regulation of synaptotagmin by THz waves remains an unclear issue. In this research, we use density functional theory and molecular dynamics simulations to calculate the THz spectra of the Ca²⁺ binding site and to identify the microscopic vibrational modes corresponding to the characteristic spectral peaks. Through molecular dynamics simulations, we find that 54.65 THz electromagnetic wave stimulation can influence the binding strength of Ca²⁺ to the synaptotagmin pocket and significantly alter the conformation of synaptotagmin. These findings suggest a possible mechanism for THz-mediated modulation of Ca²⁺-dependent protein dynamics at the molecular level.