LIP-EL222
| Type: | Synthetic promoter; Optogenetic promoter |
| Other names: | / |
| Description: | El222 is a prokaryotic transcription factor that contains a light responsive LOV domain. It has been adapted for use in many organisms such as yeast, zebrafish, and mammalian cell lines1,2,3 by fusing it to the transcriptional activation domain VP16 and a nuclear localization sequence. When exposed to blue light (≈ 465 nm), El222 dimerizes and recognizes its binding sites4. These binding sites are typically placed upstream of a minimal promoter1,2. We refer to the whole promoter, introduced in ref.2 as LIP (“light-inducible promoter”). El222 incorporates flavin-mononucleotide as chromophore, which is naturally occurring in budding yeast. A recent version of LIP has been built using the GAL1 promoter with the Gal4 activator binding sites deleted5 instead of the minimal promoter, which we refer to as GLIP (“GAL1pr-based light-inducible promoter”). |
| Organism of origin: | The light-responsive prokaryotic transcription factor EL222 and its binding sites come from Erythrobacter litoralis. The transactivation domain which adapts it for eukaryotes comes from the herpes virus (Herpes simplex) protein VP16. |
| Available on Addgene: | / |
| Inducing condition: | Blue light (≈ 465 nm) |
| Non-inducing condition: | Darkness |
Promoter name Leakiness [% maxGAL1] tau-on [min] tau-off* [min] Maximal induction level [maxGAL1] Stationary induction level [maxGAL1] Initial induction speed [0.001 maxGAL1/min] Degradation rate* [0.01/min]
LIP-EL222 80% 0.16 2.2 12.6 0.73 0.60 3.1 1.1
LIP-EL222 20% 0.16 1.3 < 1 0.20 0.16 1.3 1.0
*t-off and degradation rate were determined using ymScarletI as a reporter.
References:
- Zhao, E. M., Zhang, Y., Mehl, J., Park, H., Lalwani, M. A., Toettcher, J. E. & Avalos, J. L. Optogenetic regulation of engineered cellular metabolism for microbial chemical production. Nature 555, 683–687 (2018). https://doi.org/10.1038/nature26141
- Motta-Mena, L. B., Reade, A., Mallory, M. J., Glantz, S., Weiner, O. D., Lynch, K. W. & Gardner, K. H. An optogenetic gene expression system with rapid activation and deactivation kinetics. Nat. Chem. Biol. 10, 196–202 (2014). https://doi.org/10.1038/nchembio.1430
- Reade, A., Motta-Mena, L. B., Gardner, K. H., Stainier, D. Y., Weiner, O. D. & Woo, S. TAEL: A zebrafish-optimized optogenetic gene expression system with fine spatial and temporal control. Development dev.139238 (2016). doi:10.1242/dev.139238 https://doi.org/10.1242/dev.139238
- Zoltowski, B. D., Motta-Mena, L. B. & Gardner, K. H. Blue light-induced dimerization of a bacterial LOV–HTH DNA-binding protein. Biochemistry 52, 6653–6661 (2013). https://doi.org/10.1021/bi401040m
- Benzinger, D. & Khammash, M. Pulsatile inputs achieve tunable attenuation of gene expression variability and graded multi-gene regulation. Nat. Commun. 9, 3521 (2018). https://doi.org/10.1038/s41467-018-05882-2