8T5S

Cryo-EM structure of DRH-1 helicase and C-terminal domain bound to dsRNA

Summary for 8T5S

• Entry DOI: 10.2210/pdb8t5s/pdb
• EMDB information: 41060
• Descriptor: Dicer-related helicase, RNA (30-MER), ZINC ION, ... (6 entities in total)
• Functional Keywords: helicase, rlr, rig-i-like receptor, atpase, dsrna, antiviral protein-rna complex, antiviral protein/rna
• Biological source: Caenorhabditis elegans; More
• Total number of polymer chains: 3
• Total formula weight: 144643.53

Authors

Consalvo, C.D.,Donelick, H.M.,Shen, P.S.,Bass, B.L. (deposition date: 2023-06-14, release date: 2024-05-15, Last modification date: 2024-05-29)

Primary citation

Consalvo, C.D.,Aderounmu, A.M.,Donelick, H.M.,Aruscavage, P.J.,Eckert, D.M.,Shen, P.S.,Bass, B.L.
Caenorhabditis elegans Dicer acts with the RIG-I-like helicase DRH-1 and RDE-4 to cleave dsRNA.
Elife, 13:-, 2024

PubMed Abstract: Invertebrates use the endoribonuclease Dicer to cleave viral dsRNA during antiviral defense, while vertebrates use RIG-I-like Receptors (RLRs), which bind viral dsRNA to trigger an interferon response. While some invertebrate Dicers act alone during antiviral defense, Dicer acts in a complex with a dsRNA binding protein called RDE-4, and an RLR ortholog called DRH-1. We used biochemical and structural techniques to provide mechanistic insight into how these proteins function together. We found RDE-4 is important for ATP-independent and ATP-dependent cleavage reactions, while helicase domains of both DCR-1 and DRH-1 contribute to ATP-dependent cleavage. DRH-1 plays the dominant role in ATP hydrolysis, and like mammalian RLRs, has an N-terminal domain that functions in autoinhibition. A cryo-EM structure indicates DRH-1 interacts with DCR-1's helicase domain, suggesting this interaction relieves autoinhibition. Our study unravels the mechanistic basis of the collaboration between two helicases from typically distinct innate immune defense pathways.

PubMed: 38747717
DOI: 10.7554/eLife.93979

Experimental method

ELECTRON MICROSCOPY (2.9 Å)