Fusion proteins comprising an intein polypeptide and methods of use thereof

The composition of claim 23, wherein the first fusion protein and/or the second fusion protein further comprises a reverse transcriptase.

The composition of claim 23, wherein the first Cas12a polypeptide and/or the second Cas12a polypeptide comprises about 175, 310, 406, 441, or 550 consecutive amino acids of a Cas12a protein.

The composition of claim 23, wherein the first Cas12a polypeptide and/or the second Cas12a polypeptide has at least 70% sequence identity to one or more of SEQ ID NOs:150-159 and 175-184.

The composition of claim 23, wherein the first fusion protein and/or the second fusion protein has at least 70% sequence identity to one or more of SEQ ID NOs:100-109 or 188.

-22. (canceled)

A composition comprising:

• a first fusion protein that comprises a first Cas12a polypeptide fused to a first intein polypeptide;
• and
• a second fusion protein that comprises a second Cas12a polypeptide fused to a second intein polypeptide.

-28. (canceled)

A method of modifying a target nucleic acid, the method comprising:

• introducing a first nucleic acid molecule and a second nucleic acid molecule into a cell comprising the target nucleic acid, wherein the first nucleic acid molecule encodes a first fusion protein, the first fusion protein comprising a first Cas12a polypeptide fused to a first intein polypeptide and the second nucleic acid molecule encodes a second fusion protein, the second fusion protein comprising a second Cas12a polypeptide fused to a second intein polypeptide;
• contacting the target nucleic acid in the cell with a guide nucleic acid and a protein comprising at least a portion of the first Cas12a polypeptide and at least a portion of the second Cas12a polypeptide,
• optionally wherein the protein and the guide nucleic acid form a complex or are comprised in a complex, thereby modifying the target nucleic acid.

-32. (canceled)

(canceled)

-41. (canceled)

An engineered protein comprising an amino acid sequence that has at least 70% sequence identity to one or more of SEQ ID NOs:100-109 and 187-188.

-69. (canceled)

A method of modifying a target nucleic acid, the method comprising:

• introducing a first nucleic acid molecule and a second nucleic acid molecule into a cell comprising the target nucleic acid, wherein the first nucleic acid molecule encodes a first fusion protein, the first fusion protein comprising a polypeptide of interest fused to a first intein polypeptide and the second nucleic acid molecule encodes a second fusion protein, the second fusion protein comprising a Cas12a polypeptide fused to a second intein polypeptide;
• contacting the target nucleic acid in the cell with a guide nucleic acid (e.g., a guide RNA) and a protein comprising at least a portion of the polypeptide of interest and at least a portion of the Cas12a polypeptide,
• optionally wherein the protein and the guide nucleic acid form a complex or are comprised in a complex, thereby modifying the target nucleic acid.

-73. (canceled)

-81. (canceled)