Abstract: In some aspects, promoters, vectors, and methods of selectively inducing expression in subtypes of neuronal cells are provided. In some embodiments, single promoters can be used to restrict access to sub-populations of neurons. In some embodiments, single promoters active in different sub-populations of neurons can be used together to access a larger sub-population of neurons than either promoter alone (“set summation”).

Abstract: Cells are rendered sensitive to stimulation by introducing into a non-photoreceptor cell nucleic acid sequences encoding at least an opsin gene product, an arrestin gene product, and the alpha subunit of the heterotrimeric G protein of the Gq family. The introduced sequences are expressed by the cell to yield at least the opsin gene product, the arrestin gene product, and the alpha subunit of the heterotrimeric G protein of the Gq family. Retinal or a derivative thereof capable of bonding with the opsin gene product to form a rhodopsin is provided to the cell. The cell is then irradiated with light having a wavelength capable of converting the rhodopsin to metarhodopsin. The conversion of rhodopsin to metarhodopsin triggers a cascade of intracellular responses within the cell resulting in an increased intracellular concentration of IP3 and calcium ions.

Abstract: Method for rendering a cell sensitive to stimulation. In a preferred embodiment, the method comprises introducing, into a cell, nucleic acid sequences encoding at least an opsin gene product, an arrestin gene product, and the alpha subunit of the heterotrimeric G protein of the Gq family. The introduced nucleic acid sequences are then expressed by the non-photoreceptor cell to yield at least the opsin gene product, the arrestin gene product, and the alpha subunit of the heterotrimeric G protein of the Gq family. Retinal or a derivative thereof capable of bonding with the opsin gene product to form a rhodopsin is then provided to the non-photoreceptor cell. The non-photoreceptor cell is then irradiated with light having a wavelength capable of converting the rhodopsin to metarhodopsin. The conversion of rhodopsin to metarhodopsin triggers a cascade of intracellular responses within the cell resulting in an increased intracellular concentration of IP3 and calcium ions leading to an action potential in the cell.