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Developing ABEmax-NG with Precise Targeting and Expanded Editing Scope to Model Pathogenic Splice Site Mutations In Vivo.

ABSTRACT: RNA splicing is related to many human diseases; however, lack of efficient genetic approaches to modulate splicing has prevented us from dissecting their functions in human diseases. Recently developed base editors (BEs) offer a new strategy to modulate RNA splicing by converting conservative splice sites, but it is limited by the editing precision and scope. To overcome the limitations of currently available BE-based tools, we combined SpCas9-NG with ABEmax to generate a new BE, ABEmax-NG. We demonstrated that ABEmax-NG performed precise A⋅T to G⋅C conversion with an expanded scope, thus covering many more splicing sites. Taking advantage of this tool, we precisely achieved A⋅T to G⋅C conversion exactly at the splice sites. We further modeled pathogenic RNA splicing in vitro and in vivo. Taken together, we successfully generated a versatile tool suitable for precise and broad editing at the splice sites.

SUBMITTER: Huang S

PROVIDER: S-EPMC6548941 | biostudies-literature |

REPOSITORIES: biostudies-literature

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