Metabolically stabilized double stranded mRNA
Double stranded mRNA (ds mRNA), e.g., produced in vitro, where one strand encodes a protein of interest and the other strand is hydrogen bonded to at least a portion of the coding region for the protein, as well as methods of making and using the ds mRNA, are provided.
1. Synthetic double stranded (ds) mRNA comprising one strand of RNA encoding a therapeutic or prophylactic protein, wherein at least one strand of the ds mRNA has a 5′ cap, a start codon, a polyA sequence and encodes the protein, wherein the two strands of the ds mRNA are hydrogen bonded over at least 50% of the length of the strands, wherein the hydrogen bonded region includes at least a portion of the coding region for the protein.
2. The synthetic ds mRNA of claim 1 wherein at least one strand includes one or more non-natural nucleotides and wherein the two strands of the ds mRNA are hydrogen bonded over at least 80% of the length of the strands.
3. The synthetic ds mRNA of claim 2 wherein at least one of the non-natural nucleotides has a non-natural sugar, at least one of the non-natural nucleotides has a non-natural nucleobase, or a combination thereof.
4. The synthetic ds mRNA of claim 2 which includes 5-formyl cytidine or pseudouridine.
5. The synthetic ds mRNA of claim 2 wherein at least 5% of the nucleotides are non-natural nucleotides.
6. The synthetic ds mRNA of claim 2 wherein the non-natural nucleotide analog is a purine analog.
7. The synthetic ds mRNA of claim 1 wherein at least one strand includes at least one non-phosphodiester bond.
8. The synthetic ds mRNA of claim 1 wherein one of the strands is no more than 5 kb in length.
9. The synthetic ds mRNA of claim 1 wherein at least one strand has two or more different non-natural nucleotides.
10. A method of making a double stranded (ds) mRNA encoding a prophylactic or therapeutic protein, comprising: providing a strand of mRNA having a 5′ cap, a start codon, a polyA sequence and an open reading frame for the protein; providing a strand of RNA that has sequence complementarity with the mRNA over at least 50% of the length of the strands, wherein the hydrogen bonded region includes at least a portion of the coding region for the protein; and allowing the snRNA and the RNA with sequence complementarity to form hydrogen bond, thereby providing the ds mRNA.
11. The method of claim 10 wherein one or more nucleotide modifications are introduced post-synthesis to at least one of the strands.
12. The method of claim 10 wherein one or more non-natural nucleotides are incorporated during synthesis to at least one of the strands.
13. The method of claim 10 wherein the strands are hydrogen bonded over at least 90% of the length of the strands.
14. The method of claim 10 wherein the strands are not the same length.