Multi-photon interactions with ion-channels: From high-resolution control of neuronal activity to possible mechanisms of quantum coherence assisted ion-transport
Ion-channels are involved in many physiological processes, including maintenance of membrane potential, regulation of electrical excitability, and modulation of hormone and neurotransmitter secretion. In the nervous system their coordinated opening and closing generates action potentials that form the basis for intra-neural communication which are essential for information representation and processing. As a result they have been subject to extensive fundamental studies aiming to understand their structure and function as well as to interfere with their function in order to control neuronal response. The latter has recently proven to be a valuable tool for understanding neuronal connectivity. In these approaches optogenetic techniques are used for on demand opening of light gated ion-channels which allow the interrogation of neuronal response in functional networks.
However, most of the current methods are limited to evoking only neuronal response in large cellular population in an untargeted fashion. In this talk I will present some of our recent results on evoking targeted compartmental specific neuronal response with sub-millisecond temporal resolution by combing optogenetic methods with two-photon absorption from femtosecond optical pulses. The unprecedented spatiotemporal resolution of this method and its ability to enable high throughput pair recordings is expected to allow a new range of studies in neuronal circuitry and mechanisms of neuronal input integration on the single cell level. Further, I will discuss the application of ultrafast correlation spectroscopy methods to studies of conformational dynamics of protein complexes underlying function of the voltage gated ion-channels. In this context I will present estimations and discuss the possibility of a vibrational coherence assisted ion transport process and how the associated protein dynamics could potentially be experimentally revealed.