RNA-guided nucleases and DNA binding proteins
Compositions and methods related to Cas proteins, nucleic acids encoding the Cas proteins, and modified host cells comprising the Cas proteins and/or encoding nucleic acids are disclosed. Cas proteins are useful in a variety of applications. Cas proteins bind guide RNAs that in turn provide functional specificity to the Cas proteins, nucleic acids encoding the Cas guide RNAs, and modified host cells comprising the Cas guide RNAs and/or encoding nucleic acids. The Cas polypeptides and corresponding guide RNAs can be used in a variety of applications.
1. A composition comprising:
a) a CasMG2 fusion polypeptide comprising a CasMG2 polypeptide fused to a heterologous polypeptide or a nucleic acid molecule encoding the CasMG2 fusion polypeptide, wherein the CasMG2 polypeptide has 90% or more identity to the amino acid sequence set forth in SEQ ID NO: 59, and wherein the CasMG2 fusion polypeptide comprises the RuvC-I domain of SEQ ID NO: 63, the RuvC-II domain of SEQ ID NO: 64, and the RuvC-III domain of SEQ ID NO 65; and
b) a CasMG2 guide RNA, or one or more DNA molecules encoding the CasMG2 guide RNA, wherein the CasMG2 guide RNA comprises a guide sequence with complementarity to a eukaryotic nucleic acid;
wherein the CasMG2 polypeptide or a nucleic acid molecule encoding said polypeptide is respectively combined with the CasMG2 guide RNA or with one or more DNA molecules encoding the guide RNA.
2. The composition of claim 1 , wherein the CasMG2 polypeptide comprises an amino acid sequence having 95%, 97%, 98%, 99%, 99.5%, 99.8%, 99.9%, or more identity to the amino acid sequence set forth in SEQ ID NO: 59.
3. The composition of claim 1 , wherein the CasMG2 guide RNA is a single guide RNA.
4. The composition of claim 1 , wherein the CasMG2 guide RNA comprises an RNA encoded by SEQ ID NO: 62.
5. The composition of claim 1 , wherein the CasMG2 polypeptide is a nickase that can cleave only one strand of a double-stranded target nucleic acid molecule.
6. The composition of claim 1 , wherein the CasMG2 polypeptide is:
a catalytically inactive CasMG2 Polypeptide.
7. The composition of claim 1 , wherein:
the CasMG2 polypeptide comprises one or more mutations selected from R545K, S957A, Q981F, T1041V, N1082D, F1092Y, and/or Y1205F of SEQ ID NO: 59.
8. The composition of claim 1 , further comprising a DNA donor template.
9. A CasMG fusion polypeptide comprising a CasMG polypeptide fused to a heterologous polypeptide, wherein the CasMG polypeptide is a CasMG2 polypeptide, wherein the CasMG2 polypeptide has 90% or more identity to the amino acid sequence set forth in SEQ ID NO: 59, and wherein the CasMG2 fusion polypeptide comprises the RuvC-I domain of SEQ ID NO: 63, the RuvC-II domain of SEQ ID NO: 64, and the RuvC-III domain of SEQ ID NO 65.
10. The CasMG fusion polypeptide of claim 9 , wherein the CasMG polypeptide comprises:
a CasMG2 amino acid sequence having 95% or more identity to the amino acid sequence set forth in SEQ ID NO: 59.
11. The CasMG fusion polypeptide of claim 9 , wherein the heterologous polypeptide is operably linked to the N-terminus and/or the C-terminus of the CasMG polypeptide.
12. The CasMG fusion polypeptide of claim 9 , wherein the heterologous polypeptide comprises a nuclear localization signal.
13. The CasMG fusion polypeptide of claim 9 , wherein the heterologous polypeptide exhibits an enzymatic activity that modifies target DNA or a target polypeptide associated with a target nucleic acid.
14. The CasMG fusion polypeptide of claim 9 , wherein the heterologous polypeptide protein increases or decreases transcription of a gene when the CasMG fusion polypeptide is bound to the gene and a guide RNA.
15. A nucleic acid molecule encoding the CasMG fusion polypeptide of claim 9 .
16. A eukaryotic cell comprising:
a) a CasMG fusion polypeptide of claim 9 or a nucleic acid molecule encoding the CasMG fusion polypeptide, wherein the CasMG fusion polypeptide is a CasMG2 fusion polypeptide, and/or
b) a CasMG guide RNA of or a nucleic acid molecule encoding the CasMG guide RNA, wherein the CasMG guide RNA is a CasMG2 guide RNA;
wherein the eukaryotic cell is a plant cell, an algal cell, a fungal cell, an invertebrate cell, an ungulate cell, an avian cell, a fish cell, an amphibian cell, a reptile cell, a parasite cell, a rodent cell, a canine cell, a feline cell, a non-human primate cell, or an artificial cell.
17. A method of modifying a target nucleic acid, the method comprising contacting the target nucleic acid with:
a) a CasMG fusion polypeptide, wherein the CasMG fusion polypeptide is a CasMG2 fusion polypeptide, wherein the CasMG2 polypeptide has 90% or more identity to the amino acid sequence set forth in SEQ ID NO: 59, and wherein the CasMG2 fusion polypeptide comprises the RuvC-I domain of SEQ ID NO: 63, the RuvC-II domain of SEQ ID NO: 64, and the RuvC-III domain of SEQ ID NO 65; and
b) a CasMG guide RNA comprising a guide sequence that hybridizes to a target sequence of the target nucleic acid, wherein the CasMG guide RNA is a CasMG2 guide RNA, wherein said contacting results in modification of the target nucleic acid by the CasMG polypeptide.
18. The method of claim 17 , wherein the CasMG fusion polypeptide comprises:
a CasMG2 amino acid sequence having 95% or more identity to the amino acid sequence set forth in SEQ ID NO: 59.
19. The method of claim 17 , wherein said contacting comprises: introducing into a cell: (a) the CasMG fusion polypeptide, or a nucleic acid molecule encoding the CasMG fusion polypeptide, and (b) the CasMG guide RNA, or a nucleic acid molecule encoding the CasMG guide RNA.
20. The method of claim 17 , wherein:
the CasMG2 guide RNA comprises SEQ ID NO: 62.