Methods and compositions for simultaneous editing of both strands of a target double-stranded nucleotide sequence
The present disclosure provides systems, compositions, and methods for simultaneously editing both strands of a double-stranded DNA sequence at a target site to be edited. Further provided herein are pharmaceutical compositions, polynucleotides, vectors, cells, and kits for simultaneously editing both strands of a double-stranded DNA sequence.
1. A system for simultaneously editing both strands of a double-stranded DNA sequence at a target site to be edited, said system comprising:
(a) a prime editor or one or more polynucleotides encoding the prime editor, wherein the prime editor comprises a nucleic acid programmable DNA binding protein (napDNAbp) and a polypeptide comprising an RNA-dependent DNA polymerase activity, wherein the napDNAbp comprises a RuvC nuclease domain and a HNH nuclease domain, and wherein the HNH nuclease domain comprises one or more mutations that decrease or eliminate its nuclease activity;
(b) a first prime editing guide RNA (first PEgRNA) or one or more polynucleotides encoding the first PEgRNA, wherein the first PEgRNA comprises
(i) a first spacer sequence that is complementary to a first binding site on a first strand of the double-stranded DNA sequence upstream of the target site relative to the second strand,
(ii) a first gRNA core that is capable of complexing with the prime editor,
(iii) a first DNA synthesis template that encodes a first single-stranded DNA sequence, and
(iv) a first primer binding site complementary to a region of the second strand upstream of a first cut site; and
(c) a second prime editing guide RNA (second PEgRNA) or one or more polynucleotides encoding the second PEgRNA, wherein the second PEgRNA comprises
(i) a second spacer sequence that is complementary to a second binding site on a second strand of the double-stranded DNA sequence downstream of the target site relative to the second strand;
(ii) a second gRNA core that is capable of complexing with the prime editor,
(iii) a second DNA synthesis template that encodes a second single-stranded DNA sequence, and
(iv) a second primer binding site complementary to a region of the first strand upstream of a second cut site;
wherein the prime editor is capable of cleaving the first strand at the a-first cut site when complexed with the second PEgRNA and cleaving the second strand at the a-second cut site when complexed with the first PEgRNA,
wherein the first single-stranded DNA sequence and the second single-stranded DNA sequence are reverse complements over a region of complementarity of each single-stranded DNA sequence of
at least 5 nucleotides in length, and
wherein the first single-stranded DNA sequence comprises a first edit compared to the second strand of the target site that starts at a position no more than 3 nucleotides from the first cut site.
2. The system of claim 1 , wherein the second single-stranded DNA sequence comprises a second edit compared to the first strand of the target site that starts at a position no more than 3 nucleotides from the second cut site.
3. The system of claim 2 , wherein the region of complementarity of the first single-stranded DNA sequence and the second single-stranded DNA sequence forms a duplex comprising the first edit and the second edit.
4. The system of claim 2 , wherein the second edit comprises an insertion, a deletion, a substitution, or a combination thereof.
5. The system of claim 2 , wherein the first edit or the second edit comprises a recombinase recognition sequence.
6. The system of claim 5 , further comprising a recombinase capable of recognizing the recombinase recognition sequence, or one or more polynucleotides encoding the recombinase.
7. The system of claim 6 , wherein the recombinase is a serine recombinase.
8. The system of claim 6 , wherein the recombinase is Bxb1.
9. The system of claim 6 , wherein the recombinase recognition sequence comprises SEQ ID NO: 536 or SEQ ID NO: 537.
10. The system of claim 6 further comprising a donor template or a polynucleotide encoding the donor template.
11. The system of claim 10 , wherein the recombinase recognition sequence comprises SEQ ID NO: 536 and the donor template comprises SEQ ID NO: 537, or wherein the recombinase recognition sequence comprises SEQ ID NO: 537 and the donor template comprises SEQ ID NO: 536.
12. The system of claim 2 , wherein the second edit starts at a position no more than 2 nucleotides from the second cut site.
13. The system of claim 2 , wherein the second edit starts at the second cut site.
14. The system of claim 1 , wherein the region of complementarity encompasses the 3′ ends of the first and second single-stranded DNA sequences.
15. The system of claim 14 , wherein the region of complementarity is from 22 to 38 nucleotides in length.
16. The system of claim 15 , wherein the first edit comprises a recombinase recognition sequence.
17. The system of claim 16 , wherein the recombinase recognition sequence comprises SEQ ID NO: 536 or SEQ ID NO: 537.
18. The system of claim 1 , wherein the region of complementarity is at least 10 nucleotides in length.
19. The system of claim 1 , wherein the region of complementarity is from 22 to 38 nucleotides in length.
20. The system of claim 14 , wherein the region of complementarity is at least 10 nucleotides in length.
21. The system of claim 1 , wherein the first single-stranded DNA sequence is the reverse complement of the second single-stranded DNA sequence.
22. The system of claim 1 , wherein the first edit comprises an insertion, a deletion, a substitution, or a combination thereof.
23. The system of claim 1 , wherein the first single-stranded DNA sequence and the second single-stranded DNA sequence have the same length.
24. The system of claim 1 , wherein the first edit starts at a position no more than 2 nucleotides from the first cut site.
25. The system of claim 1 , wherein the first edit starts at the first cut site.
26. The system of claim 1 , wherein the first single-stranded DNA sequence and/or the second single-stranded DNA sequence does not comprise sequence homology as compared to the DNA sequence at the target site.
27. The system of claim 1 , wherein the napDNAbp comprises an amino acid sequence of any one of SEQ ID NOs: 18, 21, 23, 25-39, 42-61, 75, and 77-88, or an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 99% sequence identity with any one of SEQ ID NOs: 18, 21, 23, 25-39, 42-61, 75, and 77-88.
28. The system of claim 1 , wherein the polypeptide comprising the RNA-dependent DNA polymerase activity is a reverse transcriptase.
29. The system of claim 1 , wherein the polypeptide comprising the RNA-dependent DNA polymerase activity comprises an amino acid sequence of any one of SEQ ID NOs: 89-100, 106-122, 128, 132, 139, 143, 149, 154, 159, 700-736, 738-742, and 763-766, or an amino acid sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 99% sequence identity with any one of SEQ ID NOs: 89-100, 106-122, 128, 132, 139, 143, 149, 154, 159, 700-736, 738-742, and 763-766.