The present invention provides an isolated nucleic acid molecule comprising, or consisting of, the nucleic acid sequence of SEQ ID NO:1 or a nucleic acid sequence of at least 1400 bp having at least 80% identity to said sequence of SEQ ID NO:1, wherein said isolated nucleic acid molecule specifically leads to the expression in cells expressing glial fibrillary acidic protein of a gene when operatively linked to a nucleic acid sequence coding for said gene.

Disclosed herein include methods, compositions, and kits suitable for use in calcium imaging. There are provided, in some embodiments, Ca.sup.2+-sensing GvpC proteins. Disclosed herein include Ca.sup.2+-sensing gas vesicles (GVs) comprising Ca.sup.2+-sensing GvpC proteins. In some embodiments, the Ca.sup.2+-sensing GvpC protein is capable of undergoing a first allosteric conformational change upon the Ca.sup.2+-binding domain binding Ca.sup.2+ that causes the Ca.sup.2+-sensing GV to change from a GV stiff state to a GV soft state. One or more of the mechanical, acoustic, surface, and magnetic properties of a Ca.sup.2+-sensing GV can differ between the GV soft state and the GV stiff state.

Disclosed herein include methods, compositions, and kits suitable for use in calcium imaging. There are provided, in some embodiments, Ca.sup.2+-sensing GvpC proteins. Disclosed herein include Ca.sup.2+-sensing gas vesicles (GVs) comprising Ca.sup.2+-sensing GvpC proteins. In some embodiments, the Ca.sup.2+-sensing GvpC protein is capable of undergoing a first allosteric conformational change upon the Ca.sup.2+-binding domain binding Ca.sup.2+ that causes the Ca.sup.2+-sensing GV to change from a GV stiff state to a GV soft state. One or more of the mechanical, acoustic, surface, and magnetic properties of a Ca.sup.2+-sensing GV can differ between the GV soft state and the GV stiff state.

The present inventions relates to the use of an isolated nucleic acid molecule comprising a nucleotide sequence coding for a hyperpolarizing light-gated ion channel or pump gene from an archeon or for a light-active fragment of said gene, or the nucleotide sequence complementary to said nucleotide sequence, for treating or ameliorating blindness. The light-gated ion channel or pump gene can be a halorhodopsin gene.

The present inventions relates to the use of an isolated nucleic acid molecule comprising a nucleotide sequence coding for a hyperpolarizing light-gated ion channel or pump gene from an archeon or for a light-active fragment of said gene, or the nucleotide sequence complementary to said nucleotide sequence, for treating or ameliorating blindness. The light-gated ion channel or pump gene can be a halorhodopsin gene.

Provided herein are variants of an archaerhodopsin useful for application such as optical measurement of membrane potential. The present invention also relates to polynucleotides encoding the variants; nucleic acid constructs, vectors, cells comprising the polynucleotides, and cells comprising the polypeptides; and methods of using the variants.

Provided herein are variants of an archaerhodopsin useful for application such as optical measurement of membrane potential. The present invention also relates to polynucleotides encoding the variants; nucleic acid constructs, vectors, cells comprising the polynucleotides, and cells comprising the polypeptides; and methods of using the variants.

Stimulation of target cells using light, e.g., in vivo or in vitro, is implemented using a variety of methods and devices. One example involves a vector for delivering a light-activated NpHR-based molecule comprising a nucleic acid sequence that codes for light-activated NpHR-based molecule and a promoter. Either a high expression of the molecule manifests a toxicity level that is less than about 75%, or the light-activated NpHR-based proteins are expressed using at least two NpHR-based molecular variants. Each of the variants characterized in being useful for expressing a light-activated NpHR-based molecule that responds to light by producing an inhibitory current to dissuade depolarization of the neuron. Other aspects and embodiments are directed to systems, methods, kits, compositions of matter and molecules for ion pumps or for controlling inhibitory currents in a cell (e.g., in in vivo and in vitro environments).

Stimulation of target cells using light, e.g., in vivo or in vitro, is implemented using a variety of methods and devices. One example involves a vector for delivering a light-activated NpHR-based molecule comprising a nucleic acid sequence that codes for light-activated NpHR-based molecule and a promoter. Either a high expression of the molecule manifests a toxicity level that is less than about 75%, or the light-activated NpHR-based proteins are expressed using at least two NpHR-based molecular variants. Each of the variants characterized in being useful for expressing a light-activated NpHR-based molecule that responds to light by producing an inhibitory current to dissuade depolarization of the neuron. Other aspects and embodiments are directed to systems, methods, kits, compositions of matter and molecules for ion pumps or for controlling inhibitory currents in a cell (e.g., in in vivo and in vitro environments).

Presented herein, in certain embodiments, are nucleic acids and compositions for use in targeted gene editing.