8UW3

Human LINE-1 retrotransposon ORF2 protein engaged with template RNA in elongation state

8UW3 の概要

• エントリーDOI: 10.2210/pdb8uw3/pdb
• EMDBエントリー: 42637
• 分子名称: LINE-1 retrotransposable element ORF2 protein, Template RNA, Complementary DNA, ... (4 entities in total)
• 機能のキーワード: line-1, retrotransposon, reverse transcriptase, retroelement, rna binding protein, rna, rna binding protein-rna-dna complex, rna binding protein/rna/dna
• 由来する生物種: Homo sapiens (human); 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 177690.60

構造登録者

Thawani, A.,Florez Ariza, A.J.,Collins, K.,Nogales, E. (登録日: 2023-11-06, 公開日: 2023-12-20, 最終更新日: 2024-02-14)

主引用文献

Thawani, A.,Ariza, A.J.F.,Nogales, E.,Collins, K.
Template and target-site recognition by human LINE-1 in retrotransposition.
Nature, 626:186-193, 2024

PubMed Abstract: The long interspersed element-1 (LINE-1, hereafter L1) retrotransposon has generated nearly one-third of the human genome and serves as an active source of genetic diversity and human disease. L1 spreads through a mechanism termed target-primed reverse transcription, in which the encoded enzyme (ORF2p) nicks the target DNA to prime reverse transcription of its own or non-self RNAs. Here we purified full-length L1 ORF2p and biochemically reconstituted robust target-primed reverse transcription with template RNA and target-site DNA. We report cryo-electron microscopy structures of the complete human L1 ORF2p bound to structured template RNAs and initiating cDNA synthesis. The template polyadenosine tract is recognized in a sequence-specific manner by five distinct domains. Among them, an RNA-binding domain bends the template backbone to allow engagement of an RNA hairpin stem with the L1 ORF2p C-terminal segment. Moreover, structure and biochemical reconstitutions demonstrate an unexpected target-site requirement: L1 ORF2p relies on upstream single-stranded DNA to position the adjacent duplex in the endonuclease active site for nicking of the longer DNA strand, with a single nick generating a staggered DNA break. Our research provides insights into the mechanism of ongoing transposition in the human genome and informs the engineering of retrotransposon proteins for gene therapy.

PubMed: 38096901
DOI: 10.1038/s41586-023-06933-5

実験手法

ELECTRON MICROSCOPY (3.2 Å)