GEVIBench › All sensors › Jarvis
Jarvis
Variant of pAce with the ultra-bright AausFP1 fluorophore, yielding a high-contrast positive-going FRET-opsin indicator compatible with 2P voltage imaging.
- Category: eFRET GEVI
- Published: 2026-02-12 — Neuron 2026
- Derived from: pAce
- Response polarity: positive-going (fluorescence increases on depolarization)
- Spectrum: excitation peak 504 nm, emission peak 510 nm (Jarvis)
- Two-photon compatible: yes
- Tags: Ace opsin, AausFP1, Green, Positive, Two-photon
Headline values (as shown in the GEVIBench table)
| Metric | Value | Definition |
|---|---|---|
| Brightness (B/B_EGFP) | 1.39× EGFP | Molecular brightness relative to EGFP (extinction coefficient × quantum yield, or a measured ratio). Sensors not measured against EGFP directly are placed through a chain of pairwise brightness comparisons, combined by geometric mean. |
| Kinetics τ_on / τ_off (ms) | 2.7 / 1.9 ms | Activation / decay time constants in ms (amplitude-weighted mean τ for multi-exponential fits). The value shown averages the measurements made at physiological temperature (≥33 °C); if there are none, it is the measurement closest to 33 °C. |
| ΔF/F per 100 mV | +29% | Steady-state fluorescence change for a 100 mV depolarization step (−70 → +30 mV); the sign gives the polarity. The table shows the first listed measurement; the median across measurements (one-photon preferred) is used for sorting. |
| ΔF/F per mV | 0.2% (estimated from the F–V curve) | Subthreshold sensitivity: fluorescence change per mV near rest (−90 to −50 mV). Where no value is reported directly, it is estimated from the F–V curve. |
| ΔF/F per AP | 25% | Fluorescence change per single action potential in neurons. The table shows the first listed measurement; the median across measurements (one-photon preferred) is used for sorting. |
| AP width (FWHM, ms) | 1.7 ms | Full width at half maximum of the optical spike waveform. |
| Photostability t75% @ 100 mW/mm² | 2.1 min | Time for fluorescence to fall to 75% of its initial value under one-photon illumination, linearly dose-scaled to 100 mW/mm² (t50% is used where the 75% crossing falls inside a fast initial transient). Two-photon curves are not dose-scaled and are excluded. |
| Papers using it (N_used) | 1 | Number of published research papers, tracked by GEVIBench, that used the sensor for an experiment (a popularity / track-record measure). |
Measurements and sources
Kinetics
- τ_on 2.74 ms, τ_off 1.88 ms at 25°C — Grimm 2026, Fig. 1D
ΔF/F per 100 mV
- +29%, 1P — Grimm 2026, Fig. 1C(i)
ΔF/F per action potential
- 25%, 1P — Grimm 2026, Fig. 1G(ii)
AP width (FWHM)
- 1.73 ms at 1000 Hz sampling, Mouse, organotypic hippocampal slice, in vitro, 1P, 25°C — Grimm 2026, Fig. 1G(i)
Brightness comparisons
- 0.42× the brightness of pAce — Grimm 2026, Fig. 1C
- 4.08× the brightness of JEDI-2P — Grimm 2026, Fig. 1C
Photobleaching
- t75% = 317 s (extrapolated), 1P — Grimm 2026, Fig. 1F
Fluorescence–voltage (F–V) curve
ΔF/F (%) at each membrane potential, normalized to 0 at −70 mV: -90 mV: -4%; -80 mV: -2%; -70 mV: 0%; -60 mV: 2%; -50 mV: 4%; -40 mV: 7%; -30 mV: 11%; -20 mV: 14%; -10 mV: 17%; 0 mV: 21%; 10 mV: 24%; 20 mV: 26%; 30 mV: 29% — Grimm 2026, Fig. 1E
Research papers using Jarvis (1)
- Two-photon voltage imaging with rhodopsin-based sensors — Grimm C, Sims RR, Tanese D, Lafirdeen ASM, Bendifallah I, Chan CY, Faini G, Putti E, Del Bene F, Papagiakoumou E, Emiliani V, Neuron 2026 (ND7/23 cells, in vitro; CHO cells, in vitro; Mouse, organotypic hippocampal slices, in vitro; Zebrafish larvae, olfactory epithelium, in vivo)
Data and citation
- llms.txt — summary for language models
- llms-full.txt — every sensor in full (Markdown)
- gevis.json — all values and measurements with sources (JSON)
- gevis.csv — one row per sensor (CSV)
Cite GEVIBench as: Adam E. Cohen and Daozheng Gong (2026). Voltage imaging: A practical guide. Neuron. https://doi.org/10.1016/j.neuron.2026.08.002
Generated from the GEVIBench database on 2026-10-12.