National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R35GM134867
United States
National Science Foundation (NSF, United States)
2239685
United States
Citation
Journal: Nature / Year: 2025 Title: Protein-primed homopolymer synthesis by an antiviral reverse transcriptase. Authors: Stephen Tang / Rimantė Žedaveinytė / Nathaniel Burman / Shishir Pandey / Josephine L Ramirez / Louie M Kulber / Tanner Wiegand / Royce A Wilkinson / Yanzhe Ma / Dennis J Zhang / George D ...Authors: Stephen Tang / Rimantė Žedaveinytė / Nathaniel Burman / Shishir Pandey / Josephine L Ramirez / Louie M Kulber / Tanner Wiegand / Royce A Wilkinson / Yanzhe Ma / Dennis J Zhang / George D Lampe / Mirela Berisa / Marko Jovanovic / Blake Wiedenheft / Samuel H Sternberg / Abstract: Bacteria defend themselves from viral predation using diverse immune systems, many of which target foreign DNA for degradation. Defense-associated reverse transcriptase (DRT) systems provide an ...Bacteria defend themselves from viral predation using diverse immune systems, many of which target foreign DNA for degradation. Defense-associated reverse transcriptase (DRT) systems provide an intriguing counterpoint to this strategy by leveraging DNA synthesis instead. We and others recently showed that DRT2 systems use an RNA template to assemble a de novo gene that encodes an antiviral effector protein, Neo. It remains unknown whether similar mechanisms of defense are employed by other related DRT families. Focusing on DRT9, here we uncover an unprecedented mechanism of DNA homopolymer synthesis. Viral infection triggers polydeoxyadenylate (poly-dA) accumulation in the cell, driving abortive infection and population-level immunity. Cryo-EM structures reveal how a noncoding RNA serves as both a structural scaffold and reverse transcription template to direct hexameric complex assembly and poly-dA synthesis. Remarkably, biochemical and functional experiments identify tyrosine residues within the reverse transcriptase itself that likely prime DNA synthesis, leading to the formation of high-molecular weight protein-DNA covalent adducts. Synthesis of poly-dA by DRT9 in vivo is regulated by the competing activities of phage-encoded triggers and host-encoded silencers. Collectively, our work unveils a novel nucleic acid-driven defense system that expands the paradigm of bacterial immunity and broadens the known functions of reverse transcriptases.
In the structure databanks used in Yorodumi, some data are registered as the other names, "COVID-19 virus" and "2019-nCoV". Here are the details of the virus and the list of structure data.
Jan 31, 2019. EMDB accession codes are about to change! (news from PDBe EMDB page)
EMDB accession codes are about to change! (news from PDBe EMDB page)
The allocation of 4 digits for EMDB accession codes will soon come to an end. Whilst these codes will remain in use, new EMDB accession codes will include an additional digit and will expand incrementally as the available range of codes is exhausted. The current 4-digit format prefixed with “EMD-” (i.e. EMD-XXXX) will advance to a 5-digit format (i.e. EMD-XXXXX), and so on. It is currently estimated that the 4-digit codes will be depleted around Spring 2019, at which point the 5-digit format will come into force.
The EM Navigator/Yorodumi systems omit the EMD- prefix.
Related info.:Q: What is EMD? / ID/Accession-code notation in Yorodumi/EM Navigator
Yorodumi is a browser for structure data from EMDB, PDB, SASBDB, etc.
This page is also the successor to EM Navigator detail page, and also detail information page/front-end page for Omokage search.
The word "yorodu" (or yorozu) is an old Japanese word meaning "ten thousand". "mi" (miru) is to see.
Related info.:EMDB / PDB / SASBDB / Comparison of 3 databanks / Yorodumi Search / Aug 31, 2016. New EM Navigator & Yorodumi / Yorodumi Papers / Jmol/JSmol / Function and homology information / Changes in new EM Navigator and Yorodumi