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.

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.

Abstract: The disclosure provides programmable methylation “writers” and demethylation “erasers” for editing the methylation state of RNA targets, e.g., an RNA transcriptome. In particular, the disclosure provides RNA methylation editor polynucleotide contracts and vectors comprising (i) an RNA programmable RNA binding domain (RNApRNAbd); and (ii) an effector domain, wherein the effector domain is capable of adding or removing a methyl group in an RNA. The disclosed RNA methylation editor constructs are capable of achieving limited off-target modifications in RNA molecules. Further, the disclosure provides methods for making and using the programmable methylation editors to modifying the methylation state of RNA. The disclosure further provides complexes comprising a methylation writer protein and a guide RNA molecule and complexes comprising a demethylation eraser protein and a guide RNA molecule.

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. The disclosure provides fusion proteins of nucleic acid programmable DNA binding proteins (napDNAbp), e.g., Cas9 or variants thereof, and nucleic acid editing proteins such as cytidine deaminase domains (e.g., novel cytidine deaminases generated by ancestral sequence reconstruction), and adenosine deaminases that deaminate adenine in DNA. Aspects of the disclosure relate to fusion proteins (e.g., base editors) that have improved expression and/or localize efficiently to the nucleus. In some embodiments, base editors are codon optimized for expression in mammalian cells. In some embodiments, base editors include multiple nuclear localization sequences (e.g., bipartite NLSs), e.g., at least two NLSs.

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.