Attenuating ribosome load improves protein output from mRNA by limiting translation-dependent mRNA decay.

Developing an effective mRNA therapeutic often requires maximizing protein output per delivered mRNA molecule. We previously found that coding sequence (CDS) design can substantially affect protein output, with mRNA variants containing more optimal codons and higher secondary structure yielding the highest protein outputs due to their slow rates of mRNA decay. Here, we demonstrate that CDS-dependent differences in translation initiation and elongation rates lead to differences in translation- and deadenylation-dependent mRNA decay rates, thus explaining the effect of CDS on mRNA half-life.

MicroRNAs Enable mRNA Therapeutics to Selectively Program Cancer Cells to Self-Destruct.

The advent of therapeutic mRNAs significantly increases the possibilities of protein-based biologics beyond those that can be synthesized by recombinant technologies (eg, monoclonal antibodies, extracellular enzymes, and cytokines). In addition to their application in the areas of vaccine development, immune-oncology, and protein replacement therapies, one exciting possibility is to use therapeutic mRNAs to program undesired, diseased cells to synthesize a toxic intracellular protein, causing cells to self-destruct. For this approach to work, however, methods are needed to limit toxic protein expression to the intended cell type.