| abstract |
The present invention provides a novel IP3 receptor-binding protein that is used as an indicator effective for detecting and quantifying IP3, and a method for detecting and/or quantifying IP3 using the same. Determined is an IP3 receptor-binding protein, particularly a novel IP3 receptor-binding protein, IRBIT, which interacts with an IP3 receptor, and whose interaction is regulated by IP3. IRBIT has the characteristic that it can be dissociated from the IP3 receptor by IP3 at a physiological concentration. Because of this characteristic, IRBIT can be useful as an indicator for detecting IP3 by the FRET method or the like. |