Figure 5.

Interactions of between Cas13h1 and with guide-target duplex. (A) Surface representation of Cas13h1 ternary complex, with interested segments enclosed by rectangles. (B) Interaction details between Cas13h1 and guide-target RNA duplex. (C) Urea–PAGE indicating Cas13h1 RNase activity by either the wild-type Cas13h1 or the mutants of the guide-target duplex interacting residues. crRNA, target RNA1, and collateral RNA were loaded as markers. The RNAs are label-free and stained by ethidium bromide before visualization. (D) Interaction between the terminal base pairs and the ‘wedge’ residues, and interaction between 5′-G and the Heical-2 nucleotide binding pocket. (E) Structure of the 5′-U ternary complex around the 5′-end of target RNA, with cryo-EM density shown in mesh and amino acids around the nucleotide binding pocket shown in stick. (F) Superposition of the Helical-2 domains from the binary complex (blue), and ternary complex with 5′-G (gray), and the ternary complex with 5′-U (pink).