Abstract: The present invention provides, among other things, a method of producing a synthetic RNA using a self-templating approach. For example, in some embodiments a synthetic gRNA is produced comprising: contacting a first RNA with a second RNA, wherein the first RNA and the second RNA comprise at least five RNA nucleotides that are complementary, and wherein the contacting forms a stem structure or a stem loop structure, and ligating the first RNA and the second RNA with a ligating enzyme (i) within the stem structure, or (ii) at an end of the stem structure, thereby forming a loop at the end of the stem structure.

Abstract: The present disclosure relates to methods and compositions for modulating protein expression. In particular, the invention features methods and compositions for increasing protein expression in a cell by delivering to the cell a composition including an mRNA encoding a polypeptide and one or more oligonucleotides, wherein each of the one or more oligonucleotides includes a region of linked nucleotides complimentary to a portion of the sequence of the mRNA. The methods and compositions described herein may be used to modulate gene expression (e.g., increase gene expression), to increase the stability of the mRNA, to decrease the immunogenicity of the mRNA, to enable selective expression (e.g., in a target cell or tissue) of the mRNA, and/or to enable the delivery of two or more mRNAs in a stoichiometric ratio.

Abstract: The present disclosure provides messenger RNAs (mRNAs) having chemical and/or structural modifications, including RNA elements and/or modified nucleotides, in particular C-rich or CG-rich elements, which provide a desired translational regulatory activity to the mRNA.

Abstract: The present disclosure relates to methods for preparing a modified RNA comprising enzymatically ligating an acceptor moiety having a 3?-hydroxyl group to the 5?-end of a donor moiety (e.g., installation of 5?-triphosphate groups, mRNA caps, or cap-like structures on chemically synthesized RNA or installation of 5?-triphosphate groups, mRNA caps, cap-like structures, or non-cap like structures on enzymatically prepared RNA).