Zebrafish (Danio rerio) is a popular vertebrate model organism used to study the molecular mechanisms driving development and disease. Due to its transparency in the embryonic and larval stages, living organisms can be studied by subcellular resolution using a living microscope. The beneficial optical properties of zebrafish allow not only passive observation, but also active manipulation of proteins and cells through light using optogenetic tools.

Creative BioMart has been able to provide our customers with some non-neuromodulatory optogenetic tools for zebrafish to control gene expression. At present, there are three optical switches cryptochrome 2, LOV domain and BLUF domain that can be used to regulate gene expression. Based on the above switching system, we can provide zebrafish strains as follows.

Zebrafish for Gene Expression Control

The control of gene expression is conducive to exploring gene function and modeling diseases, including neurodegeneration and cancer. In zebrafish, time control is usually achieved by using a composite activation system or heat shock enhancers. The photogenetic gene expression system also provides spatial control.

Cryptochrome 2 (CRY2-CIB1)

Mechanism of action: light-induced heterodimer (or CRY2 homooigomer), disruption in dark-state Light-induced homodimer, disruption in dark-state.

Application in zebrafish: Gal4-UAS-mediated gene expression in luciferase reporter assay.

The Arabidopsis thaliana photoreceptor protein cryptochrome 2 (CRY2) interacts with cry and is illuminated by blue light after heterodimerization of basic helix loop helix (bHLH) transcription factor 1 (CIB1). This heterodimerization was used to create a photoinduced Gal4 system by fusing the GAL4 DNA binding domain with CRY2 and the GAL4 activation domain containing VP16 with CIB1. Luciferase based readings showed that using the system, blue light irradiation for 2 hours instead of red light induced luciferase expression in zebrafish.

LOV Domain

Mechanism of action: light-induced homodimer, disruption in dark-state.

Application in zebrafish: EL222 switch can be used to construct C120 promoter-mediated gene expression and be used to induce Cas9 expression for mosaic genetic knockout.

El222 is a photoinducible transcription factor containing LOV domain, which is from Ethrobacter littoralis. Blue light induces homologous dimerization of El222, and then its binding to its regulatory element activates the transcription of downstream genes. By adding nuclear localization sequence and herpes simplex virus derived VP16 transcriptional activation domain, El222 is suitable for eukaryotes to produce VP-El222. The plasmid was injected into zebrafish, which proved that blue light effectively mediated the gene expression in the system.

BLUF Domain

Mechanism of action: Dark-state heterocligomerization, light-inducod cligomer-dissociation into homodimers.

Application in zebrafish: light mediated control over the activity of dominant negative transcription factor.

The system is based on BLUF domain. The system is designed to directly control transcription factor activity through protein localization. The system contains a bacterial blue light photoreceptor that interacts with response regulatory proteins and forms oligomers in the dark. Blue light irradiation dissociates large oligomeric complexes from dimers and monomers, which is triggered by the change of protein conformation.

Creative BioMart is always devote us to provide high-quality and satisfactory service to our customers, if you are interested in our services or have some question, please feel free to contact us or make online inquiry.

Online inquiry