Calcium-activated photoprotein (e.g., Aequorin)

The term "Calcium ion indicator via photoprotein complex" does not correspond to a specific endogenous molecular target, receptor, or enzyme but rather refers to a bioluminescent protein complex, most notably represented by proteins such as aequorin or obelin. These marine photoproteins contain calcium-binding sites in EF-hand motifs; upon binding Ca²⁺, they undergo conformational changes that trigger a bioluminescent reaction, emitting blue light. This property is used extensively as a tool in cell biology for detecting and measuring intracellular calcium concentrations. Such photoproteins are introduced into cells and serve as non-toxic, genetically encodable or microinjected indicators for real-time calcium imaging. They are not drug targets, do not themselves participate in disease mechanisms, and are widely used to track dynamic calcium changes in physiological and experimental contexts[1][2][3][4][5]. Key accuracy/quality notes: - This entry is not a canonical therapeutic target such as a receptor, transporter, or enzyme, and is mainly a research tool. - If you are searching for a specific human or animal protein, please specify its full name; otherwise, this entry best describes the usage and molecular identity of these calcium-sensing photoproteins. - Major types include aequorin, obelin, and engineered fusions with fluorescent reporters (e.g., with GFP)[2][5]. - No known direct drug interactions or therapeutic relevance apart from its use as a cellular sensor for calcium[3][5]. If you need the canonical form for a specific protein photoprotein (e.g., "Aequorin"), further specificity can be provided.

Other names

Calcium ion indicatorAequorinObelinCalcium-activated photoproteinBioluminescent calcium indicatorPhotoprotein-based Ca2+ indicator