TY - JOUR TI - Sensitive red protein calcium indicators for imaging neural activity AU - Dana, Hod AU - Mohar, Boaz AU - Sun, Yi AU - Narayan, Sujatha AU - Gordus, Andrew AU - Hasseman, Jeremy P AU - Tsegaye, Getahun AU - Holt, Graham T AU - Hu, Amy AU - Walpita, Deepika AU - Patel, Ronak AU - Macklin, John J AU - Bargmann, Cornelia I AU - Ahrens, Misha B AU - Schreiter, Eric R AU - Jayaraman, Vivek AU - Looger, Loren L AU - Svoboda, Karel AU - Kim, Douglas S A2 - Häusser, Michael VL - 5 PY - 2016 DA - 2016/03/24 SP - e12727 C1 - eLife 2016;5:e12727 DO - 10.7554/eLife.12727 UR - https://doi.org/10.7554/eLife.12727 AB - Genetically encoded calcium indicators (GECIs) allow measurement of activity in large populations of neurons and in small neuronal compartments, over times of milliseconds to months. Although GFP-based GECIs are widely used for in vivo neurophysiology, GECIs with red-shifted excitation and emission spectra have advantages for in vivo imaging because of reduced scattering and absorption in tissue, and a consequent reduction in phototoxicity. However, current red GECIs are inferior to the state-of-the-art GFP-based GCaMP6 indicators for detecting and quantifying neural activity. Here we present improved red GECIs based on mRuby (jRCaMP1a, b) and mApple (jRGECO1a), with sensitivity comparable to GCaMP6. We characterized the performance of the new red GECIs in cultured neurons and in mouse, Drosophila, zebrafish and C. elegans in vivo. Red GECIs facilitate deep-tissue imaging, dual-color imaging together with GFP-based reporters, and the use of optogenetics in combination with calcium imaging. KW - GECI KW - fluorescent probes KW - calcium imaging KW - protein engineering JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -