Abstract: The presently-disclosed subject matter includes fluorescent protein-based indicators for detecting ions, small molecule analytes, or combinations thereof. In some embodiments the indicators include a polypeptide, which itself includes a fluorescent polypeptide, a compound-binding polypeptide, and a polypeptide target of the compound-binding polypeptide. In some embodiments the polypeptide includes an EosFP polypeptide, a calmodulin polypeptide, and a M13 polypeptide, or fragments and/or variants thereof. The presently-disclosed subject matter also includes methods for detecting calcium in a sample with embodiments of the present polypeptides. In some embodiments the present indicators experience a permanent shift from green to red fluorescent when exposed to an detecting substance, such as calcium.

Abstract: This disclosure provides methods for identification of olfactory sensosry neurons (OSN) that recognize specific odorants. The method comprises introducing into the OSN, a permanent activity marker which exhibits a detectable and permanent change upon activation of the neuron in response to an odorant and exposure to an exteranal stimulus, such as light. The OSN can be isolated and its receptor characterized.

Abstract: The presently-disclosed subject matter includes fluorescent protein-based indicators for detecting ions, small molecule analytes, or combinations thereof. In some embodiments the indicators include a polypeptide, which itself includes a fluorescent polypeptide, a compound-binding polypeptide, and a polypeptide target of the compound-binding polypeptide. In some embodiments the polypeptide includes an EosFP polypeptide, a calmodulin polypeptide, and a M13 polypeptide, or fragments and/or variants thereof. The presently-disclosed subject matter also includes methods for detecting calcium in a sample with embodiments of the present polypeptides. In some embodiments the present indicators experience a permanent shift from green to red fluorescent when exposed to an detecting substance, such as calcium.

Abstract: The presently-disclosed subject matter includes fluorescent protein-based indicators for detecting ions, small molecule analytes, or combinations thereof. In some embodiments the indicators include a polypeptide, which itself includes a fluorescent polypeptide, a compound-binding polypeptide, and a polypeptide target of the compound-binding polypeptide. In some embodiments the polypeptide includes an EosFP polypeptide, a calmodulin polypeptide, and a M13 polypeptide, or fragments and/or variants thereof. The presently-disclosed subject matter also includes methods for detecting calcium in a sample with embodiments of the present polypeptides. In some embodiments the present indicators experience a permanent shift from green to red fluorescent when exposed to an detecting substance, such as calcium.

Abstract: This disclosure provides methods for identification of olfactory sensosry neurons (OSN) that recognize specific odorants. The method comprises introducing into the OSN, a permanent activity marker which exhibits a detectable and permanent change upon activation of the neuron in response to an odorant and exposure to an exteranal stimulus, such as light. The OSN can be isolated and its receptor characterized.