Electronic and Ionic Conductivities of Microtubules and Actin Filaments, Their Consequences for Cell Signaling and Applications to Bioelectronics
This chapter suggests that functional electrodynamic interactions between cytoskeletal structures and ion-channels are central to the neural information processing mechanism. These interactions are supported by long-range ionic wave propagation along microtubule networks and actin filaments, and exhibit subcellular control of ionic channel activity, hence impacting the computational capabilities of the whole neural function. The chapter presents a biophysical model of nonlinear ionic wave propagation along actin filaments (AFs), supported by experimental evidence. It describes a model for a direct regulation of ion-channels and synaptic strength by AFs and networks of microtubules that control the electrical response of the dendrite in particular, and the neuron in general. The chapter provides a general overview of the structure and function of a nerve cell, emphasizing the role of cytoskeletal filaments, ion channels, and their interactions. Spines are the dendritic regions where most excitatory inputs are found, such that each spine contains one asymmetric synapse.