Molecular Tools for Targeted Control of Nerve Cell Electrical Activity. Part II

Abstract

In modern life sciences, the issue of a specific, exogenously directed manipulation of a cell’sbiochemistry is a highly topical one. In the case of electrically excitable cells, the aim of the manipulationis to control the cells’ electrical activity, with the result being either excitation with subsequent generationof an action potential or inhibition and suppression of the excitatory currents. The techniques of electricalactivity stimulation are of particular significance in tackling the most challenging basic problem: figuringout how the nervous system of higher multicellular organisms functions. At this juncture, when neuroscienceis gradually abandoning the reductionist approach in favor of the direct investigation of complex neuronalsystems, minimally invasive methods for brain tissue stimulation are becoming the basic element in thetoolbox of those involved in the field. In this review, we describe three approaches that are based on thedelivery of exogenous, genetically encoded molecules sensitive to external stimuli into the nervous tissue.These approaches include optogenetics (overviewed in Part I), as well as chemogenetics and thermogenetics(described here, in Part II), which is significantly different not only in the nature of the stimuli and structureof the appropriate effector proteins, but also in the details of experimental applications. The latter circumstanceis an indication that these are rather complementary than competing techniques.