Overview
.gif)
Actiflash is a tamoxifen-like caged-inducer, called cyclofen, that enables, upon photoactivation, the fast releasing of proteins fused to the modified estrogen receptor ligand-binding domains, ERT2. Optical-induced uncaging of Actiflash releases the fusion proteins, allowing them to translocate into the nucleus, activate transcription (using Gal4-UAS system) or induce recombination (using the Cre-lox one).
The protein expression can thus be simply controlled in time and space thanks to UV-light.
Actiflash is a great R&D tool to convert your inducible ERT model into a photo-inducible one. It is very helpful if you want to control transcription (using Gal4-UAS) or induce recombination (using Cre-lox) in space and/or time for in-vivo cell tracking experiments and more.
Visit our
glossary
for a definition of Tamoxifen.
A technology designed by
Ludovic Jullien
,
Isabelle Aujard
and
Thomas Le Saux
Published in
ChemBioChem / Molecules
Images
Features

Wide applicative scope
Technology capitalizing on the versatile use of Tamoxifen-OH for controlling functions of multiple types of proteins.

Simple conditioning
Caged Cyclofen-OH is cell-permeant and can be added either in the external medium or directly injected for conditioning.

Excellent chemical stability
Caged Cyclofen-OH does not generate any basal activation of protein function and it benefits from an excellent temporal resolution upon uncaging.

Favorable wavelength ranges for uncaging
Uncaging requires either UV-A light or a strong IR laser. Visible light is inactive, which facilitates the experiments with biological samples.

Photochemical stability
Caged Cyclofen-OH liberates Cyclofen-OH, which is photostable in contrast to Tamoxifen-OH encountering photodegradation under illumination.
Protocol
Calibration of the Actiflash concentration
It is advised to first establish the extent of phenotype sought for as a function of the Tamoxifen-OH concentration. Then the concentration of Actiflash used for sample conditioning is fixed at Tamoxifen-OH concentration causing 100% of the desired phenotype (in general 3-5 μM in cultured cells and zebrafish embryos).
Conditioning protocol with Actiflash
Incubate your samples in a serum-free medium for 90 mins, away from light.
Actiflash photoactivation
Illumination of Actiflash may be performed with UV (325-425nm range) light or multiphoton excitation (at 750 and 1064 nm with two- and three-photon excitation, respectively) to release Cyclofen-OH. You can use either benchtop UV lamps or light sources installed onmicroscopes.
The calibration of the photoactivation
The objective is to provide enough photons to exhaust the conversion of the Actiflash but without generating detrimental side-effects on the biological sample.Simply analyze the phenotype recovery with decreasing illumination duration. Then determine the shortest illumination duration leading to 100% uncaging of Actiflash.
Actiflash for Zebrafish: it is efficient with zebrafish embryos of less than 48 hpf. It does not work over 48 hpf.
Storage
Technical information

One 5mg vial
The volume of DMSO required to reach a concentration of 10mM is indicated on the vial
Want more?
We can also prepare a 50mg vial.
Ask us
for this special mice quote.
Actiflash FAQ
Actiflash Safety Datasheet
Actiflash Certificate of Analysis
Actiflash & plasmids
These 52 plasmids were developed by Sophie Vriz and Michel Volovitch in The Sophie Vriz Lab, who have the ownership of citations related to these plasmids.
These 52 plasmids are all available on Addgene.
Type | Addgene | Vriz lab name & link to Addgene | Coding sequence | Main use | Regulatory sequences |
ERT2 ready for fusion | |||||
184057 | pCSnERT(#186) | nls-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
ERT2 fused to CRE | |||||
184058 | pCSCRET2(#323) | 6myc-CRE-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184059 | pT2EFCRET(#324) | CRE-ERT2 | Zebrafish Expression | X.laevis-EF1 | |
184060 | pT2h70CRET(#325) | CRE-ERT2 | Zebrafish Expression | D.rerio-hsp70, SP6 | |
184061 | pT22iU66CriT(#387) | CRE-ERT2 | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi, SP6 | |
184062 | pT22iD36CriT(#388) | CRE-ERT2 | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Dio3 | |
ERT2 fused to Fluorescent Protein or Fluorogen-activated peptide | |||||
184063 | pCSmChnERT(#99) | mCherry-nls-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184064 | pCSKaedenERT(#100) | Kaede-nls-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184065 | pCSGFPnERT(#205) | eGFP-nls-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184066 | pT22UbGfpnE4PCh(#301) | eGFP-nls-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184067 | pT2iC6Dronpa2nlsER4(#636) | Dronpa2-2nls-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184068 | pT2iC6FAST1nls2ER4(#638) | YFAST-2nls-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
ERT2 fused to Gal4 activator | |||||
184069 | pCSTG4FER3(#190) | Gal4bdFF-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184070 | pT22gCfpUbiG4FER4P2A(#249) | Gal4bdFF-ERT2-P2A | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184071 | pT2iaTubG4FER3(#940) | Gal4bdFF-ERT2 | Zebrafish Expression | C.auratus-a1Tub | |
184072 | pT22i2Shh24G4FER3(#1041) | Gal4bdFF-ERT2 | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Shha+ABC | |
184073 | pT26CfpSox10G4FER3(#1048) | Gal4bdFF-ERT2 | Zebrafish Expression, stable transgenesis (blue heart) | D.rerio-Sox10 | |
184074 | pT26i4Gli8G4E3(#1254) | Gal4bdFF-ERT2 | Zebrafish Expression, stable transgenesis (blue heart) | D.rerio-GliRE | |
ERT2 fused to various kinases, inhibitors, redox enzymes | |||||
184075 | pCSZPKIaHAERT(#118) | ZfPKAinhiba-HA-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184076 | pCSZPKIamutHAERT(#119) | ZfmutPKAinhiba-HA-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184077 | pCSmp38ERT(#143) | 5myc-ZfP38a-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184078 | pT22U6CatalE4PCh(#767) | CatalDeltaC-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi, SP6 | |
ERT2 fused to various vertebrate transcription factors | |||||
184079 | pCSmEn2ERT(#117) | 6his-myc-chkEn2-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184080 | pCSmEn2SRERT(#231) | 6his-myc-chkEn2(SR)-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184081 | pCSmEn25EERT(#232) | 6his-myc-chkEn2(5E)-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184082 | pCSmEn2n4ERT(#234) | 6his-myc-chkEn2(n4)-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184083 | pT22gCfpUbm5En2E4PCh(#251) | 5myc-chkEn2-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184084 | pT22UbHEn2E4PCh(#262) | 3HA-chkEn2-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184085 | pT22UbhaEng2aE4PCh(#271) | 3HA-ZfEng2a-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184086 | pT22UbhaEng2bE4PCh(#272) | 3HA-ZfEng2b-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184087 | pT22Ubm5Eng2aE4PCh(#283) | 5myc-ZfEng2a-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184088 | pT22Ubm5Eng2bE4PCh(#284) | 5myc-ZfEng2b-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184089 | pT22Ubm5En2SRE4PCh(#302) | 5myc-chkEn2(SR)-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184090 | pCSm5En2CER4(#457) | 5myc-chkEn2(C>S)-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184091 | pT22Ubm4Eng2bKRPC(#493) | 4myc-ZfEng2b(WW>KK)-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184092 | pT22gcfUbm5En25EE4PCh(#552) | 5myc-chkEn2(5E)-ERT2-P2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184093 | pCSm5En2DER4(#1062) | 5myc-chkEn2(C>D)-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184094 | pT22cUm5En2E4P3Che(#1188) | 5myc-chkEn2-ERT2-5'fP2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184095 | pT22cUm5En2SE4P3Che(#1189) | 5myc-chkEn2(C>S)-ERT2-5'fP2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184096 | pT22i5uasm5En2E4P3Che(#1208) | 5myc-chkEn2-ERT2-5'fP2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | 5xUAS, SP6 | |
184097 | pT22i5uasm5En2SE4P3Che(#1209) | 5myc-chkEn2(C>S)-ERT2-5'fP2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | 5xUAS, SP6 | |
184098 | pT22i5uasH3En2SE4P3Che(#1212) | 3HA-chkEn2(C>S)-ERT2-5'fP2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | 5xUAS, SP6 | |
184099 | pT22i5uasm5En25EE4P3Che(#1213) | 5myc-chkEn2(5E)-ERT2-5'fP2A-mCherry | Zebrafish Expression, stable transgenesis (blue eye) | 5xUAS, SP6 | |
184100 | pT2iD6Hoxa13aER4(#685) | ZfHoxa13a-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184101 | pT2iD6Hoxa13bER4(#686) | ZfHoxa13b-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
184102 | pT2iU6m5Hoxa13bE4PCh(#765) | 5myc-ZfHoxa13b-ERT2-P2A-mCherry | Zebrafish Expression | D.rerio-Ubi, SP6 | |
184103 | pCSThaP6ERT(#184) | HA-MmPax6-ERT2 | Mammalian Expression, mRNA in vitro synthesis | sCMV, SP6 | |
ERT2 fused to Caspase-9 (apoptosis actuators and sensors) | |||||
184104 | pT2iApowriter2(#336) | myr-DIAP1-5myc-tEosFP-nls'-P2A-Casp9-ERT2 | Zebrafish Expression | D.rerio-Ubi | |
184105 | pT22Apowriter2(#340) | myr-DIAP1-5myc-tEosFP-nls'-P2A-Casp9-ERT2 | Zebrafish Expression, stable transgenesis (blue eye) | D.rerio-Ubi | |
184106 | pT2iU6Apowriter2N(#355) | myr-DIAP1-5myc-tEosFP-nls'-P2A-Casp9-ERT2 | Zebrafish Expression | D.rerio-Ubi, SP6 | |
184107 | pT22iuasvApoWtEos3N(#486) | myr-DIAP1-2nls-tEosFP-nls'-P2A-Casp9-ERT2 | Zebrafish Expression, stable transgenesis (blue eye) | 4xUAS | |
184108 | pT22iuasvApoWChe(#488) | myr-DIAP1-nls'-mCherry-P2A-Casp9-ERT2 | Zebrafish Expression, stable transgenesis (blue eye) | 4xUAS |
Story
"
Once upon a time, a physicist, David Bensimon, asked a chemist, Ludovic Jullien, whether he could design a caged inducer to photocontrol protein activity in living organisms. For sure! However we also needed a biologist (Sophie Vriz) to accept the challenge to validate the caged Cyclofen-OH technology. It has been a long but so nice adventure, which has involved the tight integration of the work from many talented students, postdocs, and collaborators... Thanks to all of them!"

New projects, Idylle
Combining Actiflash
You may also like to combine Actiflash with other R&D products

Stampwell V-shape
Combine Actiflash and the Stampwell V-shape to immobilize and parallelize organoids for cell tracking

Stampwell Larvae 2
Combine Actiflash and the Stampwell Larvae 2 to immobilize and parallelize embryos for in vivo cell tracking