Fig. 3. In vitro cleavage and cell-based editing activity of AsCas12a using crRNA guides modified with 2′-F, oxepane nucleotides, and 2′-araOH.

Chemical modification patterns are illustrated with corresponding mean in vitro cleavage activity (n = 2) (a) or mean cell-based editing activity (n = 6) (b) shown to the right. Error bars are standard deviation and replicates are biological. For both panels, nucleotides of the 5′ handle that are predicted from structural data to make polar contacts through 2′-OH hydrogen bonding are indicated with red asterisks below. The base-paired stem nucleotides of the 5′ handle pseudoknot are enclosed with light gray boxes. In vitro cleavage and cell-based editing assays utilize the distinct guide sequences that are shown above each schematic. Source data are provided as a Source Data file.