7ELD

Cryo-EM structure of Arabidopsis DCL1 in complex with pri-miRNA 166f

Summary for 7ELD

• Entry DOI: 10.2210/pdb7eld/pdb
• EMDB information: 31181
• Descriptor: Endoribonuclease Dicer homolog 1, pri-miRNA 166f (2 entities in total)
• Functional Keywords: microrna, mirna, endonuclease, helicase, hydrolase, nuclease, rna-binding
• Biological source: Arabidopsis thaliana (Mouse-ear cress); More
• Total number of polymer chains: 2
• Total formula weight: 261060.12

Authors

Wei, X.,Ke, H.,Feng, Y. (deposition date: 2021-04-09, release date: 2021-08-11, Last modification date: 2024-06-05)

Primary citation

Wei, X.,Ke, H.,Wen, A.,Gao, B.,Shi, J.,Feng, Y.
Structural basis of microRNA processing by Dicer-like 1.
Nat.Plants, 7:1389-1396, 2021

PubMed Abstract: MicroRNAs (miRNAs) are short non-coding RNAs that inhibit the expression of target genes by directly binding to their mRNAs. In animals, pri-miRNAs are cleaved by Drosha to generate pre-miRNAs, which are subsequently cleaved by Dicer to generate mature miRNAs. Instead of being cleaved by two different enzymes, both cleavages in plants are performed by Dicer-like 1 (DCL1). With a similar domain architecture as human Dicer, it is mysterious how DCL1 recognizes pri-miRNAs and performs two cleavages sequentially. Here, we report the single-particle cryo-electron microscopy structures of Arabidopsis DCL1 complexed with a pri-miRNA and a pre-miRNA, respectively, in cleavage-competent states. These structures uncover the plasticity of the PAZ domain, which is critical for the recognition of both pri-miRNA and pre-miRNA. These structures suggest that the helicase module serves as an engine that transfers the substrate between two sequential cleavage events. This study lays a foundation for dissecting the regulation mechanism of miRNA biogenesis in plants and provides insights into the dicing state of human Dicer.

PubMed: 34593993
DOI: 10.1038/s41477-021-01000-1

Experimental method

ELECTRON MICROSCOPY (4.6 Å)