Fig. 3: TniQ recruitment to the Cas6-Cas7.6 interface of Cascade requires hydrophobic and electrostatic interactions.
From: Structure-guided engineering of type I-F CASTs for targeted gene insertion in human cells
a Overall view of the PseCAST QCascade complex, oriented to highlight the TniQ dimer (dark/light orange). b Magnified view of the region indicated in (a), showing how TniQ.1 (dark orange) interacts with a hydrophobic cavity on Cas6. The two visual renderings are colored either by Cas6 surface (purple, top) or hydrophobicity (bottom). c Comparison of the hydrophobic interactions between TniQ.1 and Cas6 in PseCAST (left) and VchCAST (right, PDB: 6PIJ), with residues labeled. d Normalized RNA-guided DNA integration efficiency at the genomic AAVS1 locus in HEK293T cells, as measured by amplicon sequencing. The indicated arginine point mutations were designed to perturb TniQ.1-Cas6 hydrophobic interactions. NT, non-targeting crRNA. Source data are provided as a Source Data file. e Magnified views of hydrogen bonding (top) and electrostatic (bottom) interactions between Cas7.6 (blue) and TniQ.2 helix (yellow). f Normalized RNA-guided DNA integration efficiency at the genomic AAVS1 locus in HEK293T cells, as measured by amplicon sequencing. Alanine mutations perturbing Cas7.6-TniQ interactions are generally tolerated. Source data are provided as a Source Data file. Data in (d, f) are shown as mean ± s.d. for n = 3 biologically independent samples.
