GEVIBench › All sensors › pAce
pAce
Reverse-polarity variant of Ace-mNeon2 whose fluorescence increases during depolarization, enabling dual-polarity multiplexed voltage imaging in a single color channel.
- Category: eFRET GEVI
- Published: 2022-11-04 — Science 2022
- Derived from: Ace2N-mNeon2
- Response polarity: positive-going (fluorescence increases on depolarization)
- Spectrum: excitation peak 506 nm, emission peak 517 nm (pAce)
- Two-photon compatible: yes
- Plasmid: Addgene #195523
- Tags: Ace opsin, mNeon, Green, Positive
Headline values (as shown in the GEVIBench table)
| Metric | Value | Definition |
|---|---|---|
| Brightness (B/B_EGFP) | 2.40× 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) | 0.69 / 1.2 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 | +30.5% (median of 2 measurements: +35.8%) | 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 | 0.33% (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 | 10.7% (median of 3 measurements: 19.9%) | 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) | 4.3 ms | Full width at half maximum of the optical spike waveform. |
| Photostability t75% @ 100 mW/mm² | 32 s | 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) | 7 | 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 0.69 ms, τ_off 1.18 ms at 22°C — Kannan 2022, Table S1
ΔF/F per 100 mV
- +30.5%, 1P — Kannan 2022, Table S1
- +41%, 1P — Grimm 2026, Fig. 1C(i)
ΔF/F per action potential
- 10.7%, 1P — Kannan 2022, Fig. 1I
- 43%, 1P — Grimm 2026, Fig. 1G(ii)
- 19.9%, 1P — Liu 2025, Table S2
AP width (FWHM)
- 2.9 ms at 400 Hz sampling, Mouse, V1 VIP+ interneurons, awake, in vivo, 1P, 37°C — Kannan 2022, Fig. 1I
- 5.7 ms at 1000 Hz sampling, Mouse, primary hippocampal neurons, in vitro, 1P, 22°C — Zhang 2025, Fig. 1j
Brightness comparisons
- 0.7× the brightness of Ace2N-mNeon — Kannan 2022, Fig. S11A
- 28× the brightness of ASAP4e — Lee 2024, Table S4
- 0.7692307692307692× the brightness of ElectraON — Zhang 2025, Fig. 1e
- 2.380952380952381× the brightness of Jarvis — Grimm 2026, Fig. 1C
Photobleaching
- t75% = 81 s, 1P — Grimm 2026, Fig. 1F
- t75% = 636 s at 5 mW/mm², 1P — Zhang 2025, Fig. S4h
- t75% = 68 s, 1P — Kannan 2022, Fig. S11B
- t75% = 325 s, 1P — Zhang 2025, Fig. 1h
Fluorescence–voltage (F–V) curve
ΔF/F (%) at each membrane potential, normalized to 0 at −70 mV: -150 mV: -23%; -130 mV: -19%; -110 mV: -14%; -90 mV: -8%; -70 mV: 0%; -50 mV: 5%; -30 mV: 14%; -10 mV: 20%; 10 mV: 25%; 30 mV: 31%; 50 mV: 36% — Kannan 2022, Fig. 1D
Research papers using pAce (7)
- Dual-polarity voltage imaging of the concurrent dynamics of multiple neuron types — Kannan M, Vasan G, Haziza S, Huang C, Chrapkiewicz R, Luo J, Cardin JA, Schnitzer MJ, Pieribone VA, Science 2022 (Mouse, visual cortex, in vivo; mouse, hippocampus CA1, in vivo; Drosophila, MBON and PPL1 neurons, in vivo; HEK cells, in vitro)
- Wide-field fluorescence lifetime imaging of neuron spiking and subthreshold activity in vivo — Bowman AJ, Huang C, Schnitzer MJ, Kasevich MA, Science 2023 (Drosophila, in vivo)
- Dopamine-mediated interactions between short- and long-term memory dynamics — Huang C, Luo J, Woo SJ, Roitman LA, Li J, Pieribone VA, Kannan M, Vasan G, Schnitzer MJ, Nature 2024 (Drosophila, mushroom body neurons, in vivo)
- Imaging high-frequency voltage dynamics in multiple neuron classes of behaving mammals — Haziza S, Chrapkiewicz R, Zhang Y, Kruzhilin V, Li J, Delamare G, Swanson R, Buzsáki G, Kannan M, Vasan G, Lin MZ, Zeng H, Daigle T, Schnitzer MJ, Cell 2025 (Mouse, visual cortex and hippocampus, in vivo)
- High-speed voltage imaging of action potentials in molecular layer interneurons reveals sensory-driven synchrony that augments movement — Brown ST, Holla MR, Land MA, Yang S, McDonald AJ, St-Pierre F, Raman IM, Cell Reports 2025 (Mouse, cerebellar cortex, in vivo)
- 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 (Mouse cortical neurons, in vitro; zebrafish larvae, in vivo)
- Bright and Photostable Voltage Sensors Derived from mBaoJin — Zhang H, Zhou S, Kuzmicheva TP, Subach OM, Grimm C, Eom M, Baror-Sebban S, Adam Y, Yoon YG, Emilliani V, Subach FV, Piatkevich KD, bioRxiv 2025 (HeLa cells; Mouse, primary hippocampal neurons, in vitro (benchmark comparison against ElectraON/ElectraOFF))
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.