1. Chromosomes and Gene Expression
  2. Structural Biology and Molecular Biophysics
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Human LINE-1 retrotransposition requires a metastable coiled coil and a positively charged N-terminus in L1ORF1p

  1. Elena Khazina
  2. Oliver Weichenrieder  Is a corresponding author
  1. Max Planck Institute for Developmental Biology, Germany
Research Article
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Cite this article as: eLife 2018;7:e34960 doi: 10.7554/eLife.34960


LINE-1 (L1) is an autonomous retrotransposon, which acted throughout mammalian evolution and keeps contributing to human genotypic diversity, genetic disease and cancer. L1 encodes two essential proteins: L1ORF1p, a unique RNA-binding protein, and L1ORF2p, an endonuclease and reverse transcriptase. L1ORF1p contains an essential, but rapidly evolving N-terminal portion, homo-trimerizes via a coiled coil and packages L1RNA into large assemblies. Here, we determined crystal structures of the entire coiled coil domain of human L1ORF1p. We show that retrotransposition requires a non-ideal and metastable coiled coil structure, and a strongly basic L1ORF1p amino terminus. Human L1ORF1p therefore emerges as a highly calibrated molecular machine, sensitive to mutation but functional in different hosts. Our analysis rationalizes the locally rapid L1ORF1p sequence evolution and reveals striking mechanistic parallels to coiled coil-containing membrane fusion proteins. It also suggests how trimeric L1ORF1p could form larger meshworks and indicates critical novel steps in L1 retrotransposition.

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Author details

  1. Elena Khazina

    Department of Biochemistry, Max Planck Institute for Developmental Biology, Tübingen, Germany
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3626-4422
  2. Oliver Weichenrieder

    Department of Biochemistry, Max Planck Institute for Developmental Biology, Tübingen, Germany
    For correspondence
    Competing interests
    Oliver Weichenrieder, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5818-6248


Max-Planck-Gesellschaft (Open-access funding)

  • Oliver Weichenrieder

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Stephen P Goff, Howard Hughes Medical Institute, Columbia University, United States

Publication history

  1. Received: January 10, 2018
  2. Accepted: March 21, 2018
  3. Accepted Manuscript published: March 22, 2018 (version 1)
  4. Version of Record published: May 8, 2018 (version 2)


© 2018, Khazina & Weichenrieder

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.


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