Scientists at the University of Bath and Cardiff University in UK developed
an efficient biological switch that turns on protein expression at will. The
switch enables control of genome editing tools which has the potential to
regulate a system of favorable genetic modification through the entire
populations. The results are published in Scientific Reports.
The new switching method is expected to work for any protein in any species
and utilizes an inexpensive, non-toxic amino acid similar to lysine as
switch. When the switch is turned on, it requires the presence of an amino
acid known as BOC. Unlike other switches, the novel method does not use
antibiotics, removing the risks of selecting for bacterial antibiotic
resistance. The researchers successfully employed the novel switch in both
cultured cells and in early-stage mouse embryos without any detectable
target protein expression activity in the absence of BOC.
The method used by the researchers extends a principle known as genetic code
expansion. To show this principle, the researchers used transgenic mice with
a gene that makes their skin light up under UV light. When the genetic code
expansion toolkit was present in embryos from the mice, their genomic DNA
was edited to remove the fluorescence gene in the presence of BOC. Without
BOC, there was no editing.