Original plasmids were amplified in E. coli and purified with Wizard® Plus SV Minipreps DNA Purification kit from Promega. Then, 2 μg of each plasmid was cut with Nhe1 and BamHI, ran on an agarose gel, and the higher molecular mass band was purified using Wizard® SV Gel and PCR Clean-Up kit from Promega.
Ubiquitin promoter was amplified by PCR from pENTR5′_ubi using Q5® High-Fidelity DNA Polymerase, with these primers (F: 5′-cattgaGCTAGCatggatgttttcccagtcacgacg-3′, R:5′-tgactaGGATCCtgtaaacaaattcaaagtaagat-3′) and the following thermocycling protocol: 98 °C 30′′ (98 °C 10′′, 52 °C 30′′, 72 °C 2′) X35 cycles 72 °C 2′ pENTR5′_ubi was a gift from Leonard Zon (Addgene plasmid # 27320).
The PCR product was ran on an agarose gel and the band-purified using Wizard® SV Gel and PCR Clean-Up kit from Promega.
Vectors and the ubiquitin promoter insert were ligated over night using NEB T4 DNA Ligase, in a molar ratio of 1:3, mixing 50 ng of vectors and 73 ng of insert.
The resulting plasmid was then amplified in E. coli and purified with Wizard® Plus SV Minipreps DNA Purification Promega. This final plasmid was injected into 1-cell stage embryos together with the tol2 synthetic RNA.