Abstract: Some aspects of this disclosure relate to strategies, systems, methods, compositions, and kits that are useful for production (e.g., evolution) of cytidine deaminase protein variants that are characterized by increased soluble expression and/or stability relative to the wild-type cytidine deaminase protein from which they are evolved. In some embodiments, evolved cytidine deaminase variants described by the disclosure are useful for incorporation into targeted nucleic acid editing proteins, for example in fusion proteins with a Cas9 domain or variant thereof.

Abstract: 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.

Abstract: Engineered transcriptional activator-like effectors (TALEs) are versatile tools for genome manipulation with applications in research and clinical contexts. One current drawback of TALEs is that the 5? nucleotide of the target is specific for thymine (T). TALE domains with alternative 5? nucleotide specificities could expand the scope of DNA target sequences that can be bound by TALEs. Another drawback of TALEs is their tendency to bind and cleave off-target sequence, which hampers their clinical application and renders applications requiring high-fidelity binding unfeasible. This disclosure provides methods and strategies for the continuous evolution of proteins comprising DNA-binding domains, e.g., TALE domains. In some aspects, this disclosure provides methods and strategies for evolving such proteins under positive selection for a desired DNA-binding activity and/or under negative selection against one or more undesired (e.g., off-target) DNA-binding activities.

Abstract: Some aspects of the present disclosure provide methods for evolving recombinases to recognize target sequences that differ from the canonical recognition sequences. Some aspects of this disclosure provide evolved recombinases, e.g., recombinases that bind and recombine naturally-occurring target sequences, such as, e.g., target sequences within the human Rosa26 locus. Methods for using such recombinases for genetically engineering nucleic acid molecules in vitro and in vivo are also provided. Some aspects of this disclosure also provide libraries and screening methods for assessing the target site preferences of recombinases, as well as methods for selecting recombinases that bind and recombine a non-canonical target sequence with high specificity.

Abstract: The disclosure provides fusion proteins comprising a pleckstrin homology (PH) domain and a variant of Botulinum neurotoxin E (BoNT E) protease that cleaves certain non-canonical protein targets (e.g., PTEN). Fusion proteins described in the disclosure are useful for cleaving target proteins found in a cell, that is, in an intracellular environment. Aspects of the disclosure provide methods for inhibiting PTEN amount, activity, or function in a cell or subject, the methods comprising administering to a call or subject a fusion protein described herein.

Abstract: Provided herein are systems, compositions, kits, and methods for the suppression of pain (e.g., chronic pain). Genes encoding ion channels (e.g., SCN9A) responsible for the propagation pain signals in neurons (e.g., DRG neurons) may be edited using a genome editing agent (e.g., a nucleobase editor). In some embodiments, loss-of-function ion channel mutants are generated, leading to pain suppression. In some embodiments, the genome editing agent is administered locally to the site of pain or to the nerves responsible for propagation of the pain signal.

Abstract: Some aspects of this disclosure provide compositions, strategies, systems, reagents, methods, and kits that are useful for the targeted editing of nucleic acids, including editing a single site within the genome of a cell or subject, e.g., within the human genome. In some embodiments, fusion proteins capable of inducing a cytosine (C) to guanine (G) change in a nucleic acid (e.g., genomic DNA) are provided. In some embodiments, fusion proteins of a nucleic acid programmable DNA binding protein (e.g., Cas9) and nucleic acid editing proteins or protein domains, e.g., deaminase domains, polymerase domains, and/or base excision enzymes are provided. In some embodiments, methods for targeted nucleic acid editing are provided. In some embodiments, reagents and kits for the generation of targeted nucleic acid editing proteins, e.g., fusion proteins of a nucleic acid programmable DNA binding protein (e.g., Cas9), and nucleic acid editing proteins or domains, are provided.

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 an 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.

Abstract: Provided herein are systems, compositions, and methods of introducing protective and/or loss-of-function variants of CCR5 and CCR2. Variants may be introduced using a CRISPR/Cas9-based nucleobase editor or other guide nucleotide sequence-programmable DNA binding protein domain-based fusion protein described herein. Further provided herein are compositions and methods of preventing and treating conditions related to HIV infection and progression as well as to AIDS.

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: Some aspects of this disclosure provide strategies, systems, reagents, methods, and kits that are useful for the targeted editing of nucleic acids, including editing a single site within the genome of a cell or subject, e.g., within the human genome. In some embodiments, fusion proteins of nucleic acid programmable DNA binding proteins (napDNAbp), e.g., Cpf1 or variants thereof, and nucleic acid editing proteins or protein domains, e.g., deaminase domains, are provided. In some embodiments, methods for targeted nucleic acid editing are provided. In some embodiments, reagents and kits for the generation of targeted nucleic acid editing proteins, e.g., fusion proteins of a napDNAbp (e.g., CasX, CasY, Cpf1, C2c1, C2c2, C2C3, and Argonaute) and nucleic acid editing proteins or domains, are provided.

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 an 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.

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 an 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: 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 an 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.

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.

Abstract: The disclosure provides methods and compositions for treating blood diseases/disorders, such as sickle cell disease, hemochromatosis, hemophilia, and beta-thalassemia. For example the disclosure provides therapeutic guide RNAs that target the promotor of HBG1/2 to generate point mutations that increase expression of fetal hemoglobin. As another example, the disclosure provides therapeutic guide RNAs that target mutations in HBB, Factor VIII, and HFE to treat sickle cell disease, beta-thalassemia, hemophilia and hemochromatosis. The disclosure also provides fusion proteins comprising a Cas9 (e.g., a Cas9 nickase) domain and adenosine deaminases that deaminate adenosine in DNA. In some embodiments, the fusion proteins are in complex with nucleic acids, such as guide RNAs (gRNAs), which target the fusion proteins to a DNA sequence (e.g., an HBG1 or HBG2 protmoter sequence, or an HFE, GBB, or F8 gene sequence).

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: Some aspects of this disclosure provide methods for phage-assisted continuous evolution (PACE) of proteases. Some aspects of this invention provide methods for evaluating and selecting protease inhibitors based on the likelihood of the emergence of resistant proteases as determined by the protease PACE methods provided herein. Some aspects of this disclosure provide strategies, methods, and reagents for protease PACE, including fusion proteins for translating a desired protease activity into a selective advantage for phage particles encoding a protease exhibiting such an activity and improved mutagenesis-promoting expression constructs. Evolved proteases that recognize target cleavage sites which differ from their canonical cleavage site are also provided herein.

Abstract: Some aspects of this disclosure provide compositions, methods, systems, and kits for controlling the activity of RNA-programmable endonucleases, such as Cas9, or for controlling the activity of proteins comprising a Cas9 variant fused to a functional effector domain, such as a nuclease, nickase, recombinase, deaminase, transcriptional activator, transcriptional repressor, or epigenetic modifying domain. For example, the inventive proteins provided comprise a ligand-dependent intein, the presence of which inhibits one or more activities of the protein (e.g., gRNA binding, enzymatic activity, target DNA binding). The binding of a ligand to the intein results in self-excision of the intein, restoring the activity of the protein.

Abstract: The instant specification provides for evolved base editors which overcome deficiencies of those in art (including increased efficiency and/or decreased requirement for specific sequence-context at an editing site) and which are obtained a result of a phage-assisted continuous evolution (PACE) system. In particular, the instant specification provides for evolved cytidine base editors (e.g., based on APOBEC1, CDA, or AID cytidine deaminase domains) which overcome deficiencies of those in art (including increased efficiency and/or decreased requirement for specific sequence-context at an editing site) and which are obtained a result of a phage-assisted continuous evolution (PACE) system.