VIPR系统通过非连续几何三链体实现RNA引导的DNA识别

VIPR RNA- guided DNA recognition by noncontiguous geometric triplex formation Peter H. Yoon1,2†, Trevor A. Docter1†, Zeyuan Terry Zhang2,3†, Kenneth Loi1,2, Santiago C. Lopez1,2, Luis E. Valentin- Alvarado1,2, Owen T. Tuck1,2, Stephen G. Brohawn1,3,4,5, Jennifer A. Doudna1,2,3,5,6,7,8,9* Viral interference programmable repeat (VIpr) systems use a noncontiguous code for rNA- guided transcriptional silencing. How the Vipr protein and a VIpr rNA (vrrNA) comprising alternating GGY and NN segments achieve precise DNA targeting is unknown. Here, we present 21 cryo–electron microscopy structures that help explain the mechanism of target engagement. Vipr protomers oligomerize along the vrrNA to form a right- handed helical filament, sequestering each GGY motif and positioning the adjacent NN bases for target base pairing. …