Expanded dynamic range of fluorescent indicators for Ca 2+ by circularly permuted yellow fluorescent proteins

Fluorescence resonance energy transfer (FRET) technology has been used to develop genetically encoded fluorescent indicators for various cellular functions. Although most indicators have cyan- and yellow-emitting fluorescent proteins (CFP and YFP) as FRET donor and acceptor, their poor dynamic range often prevents detection of subtle but significant signals. Here, we optimized the relative orientation of the two chromophores in the Ca(2+) indicator, yellow cameleon (YC), by fusing YFP at different angles. We generated circularly permuted YFPs (cpYFPs) that showed efficient maturation and acid stability. One of the cpYFPs incorporated in YC absorbs a great amount of excited energy from CFP in its…

• JS
  Japan Science and Technology Agency

  Award: CREST
• CR
  Core Research for Evolutional Science and Technology
• PR
  Precursory Research for Embryonic Science and Technology