36PG

VIPR Ternary Complex with a duplex dsDNA substrate, 11 subunits

Summary for 36PG

• Entry DOI: 10.2210/pdb36pg/pdb
• EMDB information: 77736
• Descriptor: SUSP1 viprRNA, Target Strand, Non-target strand, ... (4 entities in total)
• Functional Keywords: ribonucleoprotein, vipr, rna binding protein, ternary complex, rna binding protein-rna-dna complex, rna binding protein/rna/dna
• Biological source: Suspvirus SUSP1; More
• Total number of polymer chains: 14
• Total formula weight: 322240.80

Authors

Docter, T.A.,Yoon, P.H.,Zhang, Z.,Brohawn, S.G.,Doudna, J.A. (deposition date: 2026-06-24, release date: 2026-09-16, Last modification date: 2026-09-30)

Primary citation

Yoon, P.H.,Docter, T.A.,Zhang, Z.T.,Loi, K.,Lopez, S.C.,Valentin-Alvarado, L.E.,Tuck, O.T.,Brohawn, S.G.,Doudna, J.A.
VIPR RNA-guided DNA recognition by noncontiguous geometric triplex formation.
Science, 393:1236-1240, 2026

PubMed Abstract: 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. DNA binding, in which every third nucleotide is skipped, results in a gapped vrRNA-DNA hybrid helix that encircles the nontarget DNA strand to form a geometric triplex. These findings suggest that triplex-mediated target-strand handoff could enable noncontiguous and programmable RNA-guided DNA recognition in VIPR systems.

PubMed: 42752121
DOI: 10.1126/science.aei3472

Experimental method

ELECTRON MICROSCOPY (3.5 Å)