University of Leicester
Browse

Protein phosphatase 1 regulates huntingtin exon 1 aggregation and toxicity

Download (16.07 MB)
journal contribution
posted on 2017-07-06, 14:40 authored by Joana Branco-Santos, Federico Herrera, Gonçalo M. Poças, Yolanda Pires-Afonso, Flaviano Giorgini, Pedro M. Domingos, Tiago F. Outeiro
Huntington’s disease (HD) is neurodegenerative disorder caused by a polyglutamine expansion in the N-terminal region of the huntingtin protein (N17). Here, we analysed the relative contribution of each phosphorylatable residue in the N17 region (T3, S13 and S16) towards huntingtin exon 1 (HTTex1) oligomerization, aggregation and toxicity in human cells and Drosophila neurons. We used bimolecular fluorescence complementation (BiFC) to show that expression of single phosphomimic mutations completely abolished HTTex1 aggregation in human cells. In Drosophila, Mimicking phosphorylation at T3 decreased HTTex1 aggregation both in larvae and adult flies. Interestingly, pharmacological or genetic inhibition of protein phosphatase 1 (PP1) prevented HTTex1 aggregation in both human cells and Drosophila while increasing neurotoxicity in flies. Our findings suggest that PP1 modulates HTTex1 aggregation by regulating phosphorylation on T3. In summary, our study suggests that modulation of HTTex1 single phosphorylation events by PP1 could constitute an efficient and direct molecular target for therapeutic interventions in HD.

Funding

The authors thank the Bloomington Drosophila Stock Center and the Developmental Studies Hybridoma Bank for fly stocks and antibodies, respectively. The authors also thank Bioimaging Unit from Instituto de Medicina Molecular and Advance Imaging Unit from Gulbenkian Science Institute for support with imaging. TFO and FH were supported by a seed grant from the European Huntington Disease Network (EHDN). TFO is currently supported by the DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain. FH and PMD were also supported by Project LISBOA-01-0145-FEDER-007660 (Cellular Structural and Molecular Microbiology) funded by FEDER funds through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) and by national funds through Fundação para a Ciência e Tecnologia (Refs. SFRH/BPD/63530/2009, IF/00094/2013/CP1173/CT0005 and UID/CBQ/04612/2013). JBS was supported by Fundação para a Ciência e a Tecnologia (Ref. SFRH/BD/85275/2012) and FCT/MCTES (Ref. CBQ/04612/ICL3535, to FH and PMD). PMD, GMP and YPA were also supported by Fundação para a Ciência e a Tecnologia (FCT-ANR/NEUNMC/0006/2013 and PTDC/NEU-NMC/2459/2014). FG thanks the Medical Research Council (MRC) for funding that provided valuable infrastructure supporting this work.

History

Citation

Human Molecular Genetics, 2017, ddx260

Author affiliation

/Organisation/COLLEGE OF MEDICINE, BIOLOGICAL SCIENCES AND PSYCHOLOGY/MBSP Non-Medical Departments/Department of Genetics

Version

  • AM (Accepted Manuscript)

Published in

Human Molecular Genetics

Publisher

Oxford University Press (OUP)

issn

0964-6906

eissn

1460-2083

Acceptance date

2017-06-30

Copyright date

2017

Available date

2018-07-07

Publisher DOI

Publisher version

https://academic.oup.com/hmg/article/doi/10.1093/hmg/ddx260/3932276/Protein-phosphatase-1-regulates-huntingtin-exon-1

Notes

The file associated with this record is under embargo until 12 months after publication, in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above.

Language

en

Administrator link

Usage metrics

    University of Leicester Publications

    Categories

    No categories selected

    Keywords

    IR content

    Licence

    All Rights Reserved

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC