Identification of PARP-7 substrates reveals a role for MARylation in microtubule control in ovarian cancer cells

  1. Lavanya H Palavalli Parsons
  2. Sridevi Challa
  3. Bryan A Gibson
  4. Tulip Nandu
  5. MiKayla S Stokes
  6. Dan Huang
  7. Jayanthi S Lea
  8. W Lee Kraus  Is a corresponding author
  1. University of Texas Southwestern Medical Center, United States

Abstract

PARP-7 (TiPARP) is a mono(ADP-ribosyl) transferase whose proteins substrates and biological activities are poorly understood. We observed that PARP7 mRNA levels are lower in ovarian cancer patient samples compared to non-cancerous tissue, but PARP-7 protein nonetheless contributes to several cancer-related biological endpoints in ovarian cancer cells (e.g., growth, migration). Global gene expression analyses in ovarian cancer cells subjected to PARP-7 depletion indicate biological roles for PARP-7 in cell-cell adhesion and gene regulation. To identify the MARylated substrates of PARP-7 in ovarian cancer cells, we developed an NAD+ analog-sensitive approach, which we coupled with mass spectrometry to identify the PARP-7 ADP-ribosylated proteome in ovarian cancer cells, including cell-cell adhesion and cytoskeletal proteins. Specifically, we found that PARP-7 MARylates α-tubulin to promote microtubule instability, which may regulate ovarian cancer cell growth and motility. In sum, we identified an extensive PARP-7 ADP-ribosylated proteome with important roles in cancer-related cellular phenotypes.

Data availability

The RNA-seq sets generated for this study can be accessed from the NCBI's Gene Expression Omnibus (GEO) repository (http://www.ncbi.nlm.nih.gov/geo/) using the superseries accession number GSE153395. The new mass spec data sets generated for these studies are available as supplemental data provided with this manuscript. They can also be accessed from the Spectrometry Interactive Virtual Environment (MassIVE) repository (https://massive.ucsd.edu/ProteoSAFe/static/massive.jsp) using accession number MSV000086611.

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Lavanya H Palavalli Parsons

    Ob/Gyn, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    No competing interests declared.
  2. Sridevi Challa

    Signalling and Gene Regulation Laboratory, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    No competing interests declared.
  3. Bryan A Gibson

    Signalling and Gene Regulation Laboratory, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    Bryan A Gibson, Holds the patents on the anti-MAR binding reagent (United States Patent No. 9,599,606) and the asPARP technology (United States Patent No. 9,926,340) described herein. UT Southwestern Medical Center has licensed the anti-MAR binding reagent to EMD Millipore, which markets it for research purposes. BIOLOG Life Science Institute, a coholder of United States Patent No. 9,926,340, sells the NAD+ analog 8-Bu(3-yne)T-NAD+..
  4. Tulip Nandu

    Signalling and Gene Regulation Laboratory, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    No competing interests declared.
  5. MiKayla S Stokes

    Signalling and Gene Regulation Laboratory, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2144-4343
  6. Dan Huang

    Signalling and Gene Regulation Laboratory, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    No competing interests declared.
  7. Jayanthi S Lea

    Ob/Gyn, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    No competing interests declared.
  8. W Lee Kraus

    Signalling and Gene Regulation Laboratory, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, United States
    For correspondence
    LEE.KRAUS@utsouthwestern.edu
    Competing interests
    W Lee Kraus, Is a founder consultant for Ribon Therapeutics, Inc. Holds the patents on the anti-MAR binding reagent (United States Patent No. 9,599,606) and the asPARP technology (United States Patent No. 9,926,340) described herein. UT Southwestern Medical Center has licensed the anti-MAR binding reagent to EMD Millipore, which markets it for research purposes. BIOLOG Life Science Institute, a coholder of United States Patent No. 9,926,340, sells the NAD+ analog 8-Bu(3-yne)T-NAD+..
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8786-2986

Funding

National Institute of Diabetes and Digestive and Kidney Diseases (R01 DK069710)

  • W Lee Kraus

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

Reviewing Editor

  1. Anthony K. L. Leung

Publication history

  1. Received: June 27, 2020
  2. Accepted: January 20, 2021
  3. Accepted Manuscript published: January 21, 2021 (version 1)
  4. Version of Record published: February 12, 2021 (version 2)

Copyright

© 2021, Palavalli Parsons 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. Lavanya H Palavalli Parsons
  2. Sridevi Challa
  3. Bryan A Gibson
  4. Tulip Nandu
  5. MiKayla S Stokes
  6. Dan Huang
  7. Jayanthi S Lea
  8. W Lee Kraus
(2021)
Identification of PARP-7 substrates reveals a role for MARylation in microtubule control in ovarian cancer cells
eLife 10:e60481.
https://doi.org/10.7554/eLife.60481

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