Abstract: The disclosure provides modified pegRNAs comprising one or more appended nucleotide structural motifs which increase the editing efficiency during prime editing, increase half-life in vivo, and increase lifespan in a cell. Modifications include, but are not limited to, an aptamer (e.g., prequeosim-1 riboswitch aptamer or “evopreQi-1”) or a variant thereof, a pseudoknot (the MMLV viral genome pseudoknot or “Mpknot-1”) or a variant thereof, a tRNA (e.g., the modified tRNA used by MMLV as a primer for reverse transcription) or a variant thereof, or a G-quadruplex or a variant thereof. The disclosure further provides prime editor complexes comprising the modified pegRNAs and having improved characteristics and/or performance, including stability, improved cellular lifespan, and improved editing efficiency.

Abstract: Compositions and methods are provided herein for conducting prime editing of a target DNA molecule (e.g., a genome) that enables the incorporation of a nucleotide change and/or targeted mutagenesis. The compositions include fusion proteins comprising nucleic acid programmable DNA binding proteins (napDNAbp) and a polymerase (e.g., reverse transcriptase), which is guided to a specific DNA sequence by a modified guide RNA, named a PEgRNA. The PEgRNA has been altered (relative to a standard guide RNA) to comprise an extended portion that provides a DNA synthesis template sequence which encodes a single strand DNA flap which is synthesized by the polymerase of the fusion protein and which becomes incoporated into the target DNA molecule.

Abstract: The present disclosure provides compositions and methods for conducting prime editing of a target DNA molecule (e.g., a genome) that enables the incorporation of a nucleotide change and/or targeted mutagenesis. The nucleotide change can include a single-nucleotide change (e.g., any transition or any transversion), an insertion of one or more nucleotides, or a deletion of one or more nucleotides. More in particular, the disclosure provides fusion proteins comprising nucleic acid programmable DNA binding proteins (napDNAbp) and a polymerase (e.g., reverse transcriptase), which is guided to a specific DNA sequence by a modified guide RNA, named an PEgRNA.

Abstract: Compositions and methods are provided herein for conducting prime editing of a target DNA molecule (e.g., a genome) that enables the incorporation of a nucleotide change and/or targeted mutagenesis. The compositions include fusion proteins comprising nucleic acid programmable DNA binding proteins (napDNAbp) and a polymerase (e.g., reverse transcriptase), which is guided to a specific DNA sequence by a modified guide RNA, named a PEgRNA. The PEgRNA has been altered (relative to a standard guide RNA) to comprise an extended portion that provides a DNA synthesis template sequence which encodes a single strand DNA flap which is synthesized by the polymerase of the fusion protein and which becomes incorporated into the target DNA molecule.