RT Journal Article SR Electronic T1 An Expanded Palette of Genetically Encoded Ca2+ Indicators JF Science JO Science FD American Association for the Advancement of Science SP 1888 OP 1891 DO 10.1126/science.1208592 VO 333 IS 6051 A1 Zhao, Yongxin A1 Araki, Satoko A1 Wu, Jiahui A1 Teramoto, Takayuki A1 Chang, Yu-Fen A1 Nakano, Masahiro A1 Abdelfattah, Ahmed S. A1 Fujiwara, Manabi A1 Ishihara, Takeshi A1 Nagai, Takeharu A1 Campbell, Robert E. YR 2011 UL http://science.sciencemag.org/content/333/6051/1888.abstract AB Engineered fluorescent protein (FP) chimeras that modulate their fluorescence in response to changes in calcium ion (Ca2+) concentration are powerful tools for visualizing intracellular signaling activity. However, despite a decade of availability, the palette of single FP-based Ca2+ indicators has remained limited to a single green hue. We have expanded this palette by developing blue, improved green, and red intensiometric indicators, as well as an emission ratiometric indicator with an 11,000% ratio change. This series enables improved single-color Ca2+ imaging in neurons and transgenic Caenorhabditis elegans. In HeLa cells, Ca2+ was imaged in three subcellular compartments, and, in conjunction with a cyan FP–yellow FP–based indicator, Ca2+ and adenosine 5′-triphosphate were simultaneously imaged. This palette of indicators paints the way to a colorful new era of Ca2+ imaging.