[English] 日本語
Yorodumi Papers
- Database of articles cited by EMDB/PDB/SASBDB data -

+
Search query

Keywords
Structure methods
Author
Journal
IF

-
Structure paper

TitleOligomer disassembly activates an HEPN-containing bacterial defense system.
Journal, issue, pagesMol. Cell, Year 2026
Publish dateSep 25, 2025
AuthorsYiwen Tang / Ting Liu / Chao Xiong / Qiang Chen / Yamei Yu /
PubMed AbstractThe evolutionary arms race between bacteria and phages has driven the diversification of prokaryotic antiviral defense mechanisms, with nucleic acid degradation emerging as a central strategy. Here, ...The evolutionary arms race between bacteria and phages has driven the diversification of prokaryotic antiviral defense mechanisms, with nucleic acid degradation emerging as a central strategy. Here, we investigate a Higher Eukaryotes and Prokaryotes Nucleotide-binding (HEPN) domain-containing defense system from Escherichia coli that mediates RNase-dependent abortive infection. In contrast to canonical immune systems, where oligomerization triggers signaling, this system adopts a dodecameric autoinhibited architecture, with RNase activity unleashed upon oligomer dissociation. This activation mechanism is reminiscent of the dispersal of dandelion seeds, and we therefore term this defense system "Dandelion." We further identify the phage single-stranded DNA-binding (SSB) protein as a trigger for the Dandelion system, and phylogenetic analysis of SSB proteins uncovers the specificity underlying phage resistance. Our findings reveal a counterintuitive paradigm in bacterial immunity-‌oligomer disassembly as an activation switch, which challenges the long-standing dogma that protein oligomerization activates immune signaling.
External linksMol. Cell / PubMed:42349403
MethodsEM (single particle) / X-ray diffraction
Resolution1.548 - 3.33 Å
Structure data

66345
EMDB Unreleased entry

9wxf

EMDB-66345, PDB-9wxf:
cryo-electron microscopy structure of Dandelion
Method: EM (single particle) / Resolution: 3.33 Å

PDB-9wwz:
Crystal structure of CTD of Dandelion
Method: X-RAY DIFFRACTION / Resolution: 2.785 Å

PDB-9wx2:
Crystal structure of the HEPN domain of Dandelion
Method: X-RAY DIFFRACTION / Resolution: 1.548 Å

Chemicals

ChemComp-HOH:
WATER

ChemComp-MG:
Unknown entry

Source
  • escherichia coli (E. coli)
KeywordsIMMUNE SYSTEM / Dandelion / dimer / dodecamer

+
About Yorodumi Papers

-
News

-
Feb 9, 2022. New format data for meta-information of EMDB entries

New format data for meta-information of EMDB entries

  • Version 3 of the EMDB header file is now the official format.
  • The previous official version 1.9 will be removed from the archive.

Related info.:EMDB header

External links:wwPDB to switch to version 3 of the EMDB data model

-
Aug 12, 2020. Covid-19 info

Covid-19 info

URL: https://pdbj.org/emnavi/covid19.php

New page: Covid-19 featured information page in EM Navigator.

Related info.:Covid-19 info / Mar 5, 2020. Novel coronavirus structure data

+
Mar 5, 2020. Novel coronavirus structure data

Novel coronavirus structure data

Related info.:Yorodumi Speices / Aug 12, 2020. Covid-19 info

External links:COVID-19 featured content - PDBj / Molecule of the Month (242)：Coronavirus Proteases

+
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

External links:EMDB Accession Codes are Changing Soon! / Contact to PDBj

+
Jul 12, 2017. Major update of PDB

Major update of PDB

  • wwPDB released updated PDB data conforming to the new PDBx/mmCIF dictionary.
  • This is a major update changing the version number from 4 to 5, and with Remediation, in which all the entries are updated.
  • In this update, many items about electron microscopy experimental information are reorganized (e.g. em_software).
  • Now, EM Navigator and Yorodumi are based on the updated data.

External links:wwPDB Remediation / Enriched Model Files Conforming to OneDep Data Standards Now Available in the PDB FTP Archive

-
Yorodumi Papers

Database of articles cited by EMDB/PDB/SASBDB data

  • Database of articles cited by EMDB, PDB, and SASBDB entries
  • Using PubMed data

Related info.:EMDB / PDB / SASBDB / Yorodumi / EMN Papers / Changes in new EM Navigator and Yorodumi

Read more