Prosurvival long noncoding RNA PINCR regulates a subset of p53 targets in human colorectal cancer cells by binding to Matrin 3
- National Institutes of Health, United States
- University of Illinois at Urbana Champaign, United States
- Ionis Pharmaceuticals, United States
- University of Minnesota, United States
- University of Illinois at Urbana-Champaign, United States
Abstract
Thousands of long noncoding RNAs (lncRNAs) have been discovered, yet the function of the vast majority remains unclear. Here, we show that a p53-regulated lncRNA which we named PINCR (p53-induced noncoding RNA), is induced ~100-fold after DNA damage and exerts a prosurvival function in human colorectal cancer cells (CRC) in vitro and tumor growth in vivo. Targeted deletion of PINCR in CRC cells significantly impaired G1 arrest and induced hypersensitivity to chemotherapeutic drugs. PINCR regulates the induction of a subset of p53 targets involved in G1 arrest and apoptosis, including BTG2, RRM2B and GPX1. Using a novel RNA pulldown approach that utilized endogenous S1-tagged PINCR, we show that PINCR associates with the enhancer region of these genes by binding to RNA-binding protein Matrin 3 that, in turn, associates with p53. Our findings uncover a critical prosurvival function of a p53/PINCR/Matrin 3 axis in response to DNA damage in CRC cells.
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Funding
National Cancer Institute (NIH IRP)
- Ashish Lal
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All animal studies were conducted under protocol LC-070 approved by the Animal Care and Use Committee of the National Cancer Institute, The Frederick National Laboratory and the Center for Cancer Research are accredited by AALAC International and follow the Public Health Service Policy for the Care and Use of Laboratory Animals.
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This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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