Double-Lariat Caged Morpholino Oligonucleotides for Optical Gene Silencing

Caged morpholino oligonucleotides (cMOs) are synthetic tools that allow light-inducible gene silencing in live organisms. Previously reported cMOs have utilized hairpin, duplex, and cyclic structures, as well as caged nucleobases. While these optochemical technologies enable efficient optical gene silencing, they can have limited dynamic range. To address this issue, a new caging strategy was developed where the two MO termini are conjugated to an internal position through a self-immolative trifunctional linker, thereby generating a bicyclic cMO with a double lariat-like structure. The efficacy of this alternative cMO design has been demonstrated in zebrafish embryos and compared to the monocyclic constructs.