Laser-induced perturbation into molecular dynamics localized in neuronal cell

Abstract

Molecular dynamics at synaptic terminals in neuronal cells is essential for synaptic plasticity and subsequent modulation of cellular functions in a neuronal network. For realizing artificial control of living neuronal network, we demonstrate laser-induced perturbation into molecular dynamics in the neuronal cells. The optical trapping of cellular molecules such as synaptic vesicles or neural cell adhesion molecules labeled with quantum dots was evaluated by fluorescence imaging and fluorescence correlation spectroscopy. The trapping and assembling dynamics was revealed that the molecular motion was constrained at the focal spot of a focused laser beam due to optical trapping force. Our method has a potential to manipulate synaptic transmission at single synapse level.

Surface plasmon-enhanced optical trapping of quantum-dot-conjugated surface molecules on neurons cultured on a plasmonic chip

“…In a previous study, when a trapping laser at a laser power as low as 100 mW was focused on the fluorescent puncta on neuronal cells cultured on a glass-bottomed dish, the two-photon excitation fluorescence intensity of Q-dot-conjugated NCAMs at the laser focus did not increase with irradiation time, suggesting that the motion of Q-dot-conjugated NCAMs was barely affected by optical trapping. 30) In contrast, at a high laser power of 300 mW, the fluorescence intensity at the focal spot apparently increased with irradiation time. This suggests that Q-dot-conjugated NCAMs were trapped around the focal spot at the high laser power.…”