6M6Q

Crystal structure of Caenorhabditis elegans Dicer-related helicase 3 (DRH-3) N-terminal domain

Summary for 6M6Q

• Entry DOI: 10.2210/pdb6m6q/pdb
• Descriptor: Dicer Related Helicase (2 entities in total)
• Functional Keywords: rna interference (rnai), rna helicase, card, signaling protein
• Biological source: Caenorhabditis elegans
• Total number of polymer chains: 2
• Total formula weight: 79424.45

Authors

Li, K.,Zheng, J.,Wirawan, M.,Xiong, Z.,Fedorova, O.,Griffin, P.,Plyle, A.,Luo, D. (deposition date: 2020-03-16, release date: 2021-03-17, Last modification date: 2024-05-29)

Primary citation

Li, K.,Zheng, J.,Wirawan, M.,Trinh, N.M.,Fedorova, O.,Griffin, P.R.,Pyle, A.M.,Luo, D.
Insights into the structure and RNA-binding specificity of Caenorhabditis elegans Dicer-related helicase 3 (DRH-3).
Nucleic Acids Res., 49:9978-9991, 2021

PubMed Abstract: DRH-3 is critically involved in germline development and RNA interference (RNAi) facilitated chromosome segregation via the 22G-siRNA pathway in Caenorhabditis elegans. DRH-3 has similar domain architecture to RIG-I-like receptors (RLRs) and belongs to the RIG-I-like RNA helicase family. The molecular understanding of DRH-3 and its function in endogenous RNAi pathways remains elusive. In this study, we solved the crystal structures of the DRH-3 N-terminal domain (NTD) and the C-terminal domains (CTDs) in complex with 5'-triphosphorylated RNAs. The NTD of DRH-3 adopts a distinct fold of tandem caspase activation and recruitment domains (CARDs) structurally similar to the CARDs of RIG-I and MDA5, suggesting a signaling function in the endogenous RNAi biogenesis. The CTD preferentially recognizes 5'-triphosphorylated double-stranded RNAs bearing the typical features of secondary siRNA transcripts. The full-length DRH-3 displays unique structural dynamics upon binding to RNA duplexes that differ from RIG-I or MDA5. These features of DRH-3 showcase the evolutionary divergence of the Dicer and RLR family of helicases.

PubMed: 34403472
DOI: 10.1093/nar/gkab712

Experimental method

X-RAY DIFFRACTION (2.8 Å)