Part:BBa_M50101:Experience

This experience page is provided so that any user may enter their experience using this part.
Please enter how you used this part and how it worked out.

Applications of BBa_M50101

We used the optogenetic transcription factor EL-222 to drive transcription of another construct. We attached a p2A DasherGFP at the end of the other construct to infer transcription/expression activity.

Cells were transfected with these DNA constructs using Lipofectamine 3000 Reagent, Opti-MEM media, and P3000 (Thermo Fisher). Dual transfections with a maximum of 2μg of total DNA were added to each well at varying ratios of EL222 to C120-Insulin. Controls included single single transfections of EL222, C120-Insulin, GFP positive control (pHela), and a mock transfection. 24 hours post-transfection, fresh DMEM media was added. Effective transfection of pVP-EL222 was confirmed via microscopy. Light stimulation was then initiated for 24 hrs (465 nm, 8W/m^2,20s on-60s off continuous loop). Cells were kept at 37℃ and 5% CO2 during illumination.

We observed strong RFP expression in any cells with EL222 plasmid after only one day post-transfection using 1.5 ug of EL222 in our transfection.

From top to bottom: dual transfection (top), c120 only transfection (middle), el222 only (bottom)

RFP expression was retained two days post-transfection, as shown by flow-cytometry data. RFP was observed in dual transfection (blue and purple) and EL-222 only (red) cells but not in c120 only (green) or mock (grey) transfection groups.

Y-axis: Normalized Count X-axis: RFP fluorescence

Using lower amounts (> 1 ug) of EL222 in transfection may lead to very low transfection efficiency, although more rigorous testing is required to prove this claim.

Grey - Mock, Red - No Light, Purple - 24 hr light (20s on, 60s off)

After 24 hrs of lighting, we were able to observe low efficiency GFP expression in dual transfected groups, but no in any of the controls.

From top to bottom: dual transfection (top), c120 only transfection (middle), el222 only (bottom)

We conclude that VPEL222 can induce target gene expression, albeit with low efficiency (in this case). Further optimization of plasmid ratios and transfection will be needed to test this conclusion further. A stable cell line would also help tremendously in improving transfection success.

User Reviews

UNIQb136f54af66e30ca-partinfo-00000000-QINU UNIQb136f54af66e30ca-partinfo-00000001-QINU