1. Chromosomes and Gene Expression

Multi-step coordination of telomerase recruitment in fission yeast through two coupled telomere-telomerase interfaces

  1. Xichan Hu
  2. Jinqiang Liu
  3. Hyun-IK Jun
  4. Jin-Kwang Kim
  5. Feng Qiao  Is a corresponding author
  1. University of California, Irvine, United States
https://doi.org/10.7554/eLife.15470
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Cite this article
  1. Xichan Hu
  2. Jinqiang Liu
  3. Hyun-IK Jun
  4. Jin-Kwang Kim
  5. Feng Qiao
(2016)
Multi-step coordination of telomerase recruitment in fission yeast through two coupled telomere-telomerase interfaces
eLife 5:e15470.
https://doi.org/10.7554/eLife.15470
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Abstract

Tightly controlled recruitment of telomerase, a low-abundance enzyme, to telomeres is essential for regulated telomere synthesis. Recent studies in human cells revealed that a patch of amino acids in the shelterin component TPP1, called the TEL-patch, is essential for recruiting telomerase to telomeres. However, how TEL-patch-telomerase interaction integrates into the overall orchestration of telomerase regulation at telomeres is unclear. In fission yeast, Tel1ATM/Rad3ATR-mediated phosphorylation of shelterin component Ccq1 during late S phase is involved in telomerase recruitment through promoting the binding of Ccq1 to a telomerase accessory protein Est1. Here, we identify the TEL-patch in Tpz1TPP1, mutations of which lead to decreased telomeric association of telomerase, similar to the phosphorylation-defective Ccq1. Furthermore, we find that telomerase action at telomeres requires formation and resolution of an intermediate state, in which the cell cycle-dependent Ccq1-Est1 interaction is coupled to the TEL-patch-Trt1 interaction, to achieve temporally regulated telomerase elongation of telomeres.

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Author details

  1. Xichan Hu

    Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Jinqiang Liu

    Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Hyun-IK Jun

    Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Jin-Kwang Kim

    Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Feng Qiao

    Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, United States
    For correspondence
    qiao@uci.edu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2016, Hu et al.

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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  1. Xichan Hu
  2. Jinqiang Liu
  3. Hyun-IK Jun
  4. Jin-Kwang Kim
  5. Feng Qiao
(2016)
Multi-step coordination of telomerase recruitment in fission yeast through two coupled telomere-telomerase interfaces
eLife 5:e15470.
https://doi.org/10.7554/eLife.15470

Share this article

https://doi.org/10.7554/eLife.15470

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