Disruption of the Caenorhabditis elegans Integrator complex triggers a non-conventional transcriptional mechanism beyond snRNA genes

PLoS Genet. 2019 Feb 26;15(2):e1007981. doi: 10.1371/journal.pgen.1007981. eCollection 2019 Feb.

Abstract

Gene expression is generally regulated by recruitment of transcription factors and RNA polymerase II (RNAP II) to specific sequences in the gene promoter region. The Integrator complex mediates processing of small nuclear RNAs (snRNAs) as well as the initiation and release of paused RNAP II at specific genes in response to growth factors. Here we show that in C. elegans, disruption of the Integrator complex leads to transcription of genes located downstream of the snRNA loci via a non-conventional transcription mechanism based on the lack of processing of the snRNAs. RNAP II read-through generates long chimeric RNAs containing snRNA, the intergenic region and the mature mRNA of the downstream gene located in sense. These chimeric sn-mRNAs remain as untranslated long non-coding RNAs, in the case of U1- and U2-derived sn-mRNAs, but can be translated to proteins in the case of SL-derived sn-mRNAs. The transcriptional effect caused by disruption of the Integrator complex is not restricted to genes located downstream of the snRNA loci but also affects key regulators of signal transduction such as kinases and phosphatases. Our findings highlight that these transcriptional alterations may be behind the correlation between mutations in the Integrator complex and tumor transformation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Caenorhabditis elegans / embryology
  • Caenorhabditis elegans / genetics*
  • Caenorhabditis elegans / metabolism*
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism
  • Down-Regulation
  • Gene Knockdown Techniques
  • Genes, Helminth
  • Mutation
  • RNA Polymerase II / genetics
  • RNA Polymerase II / metabolism
  • RNA Processing, Post-Transcriptional
  • RNA, Helminth / genetics*
  • RNA, Helminth / metabolism*
  • RNA, Small Nuclear / genetics*
  • RNA, Small Nuclear / metabolism*
  • Signal Transduction
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Transcription, Genetic
  • Up-Regulation

Substances

  • Caenorhabditis elegans Proteins
  • RNA, Helminth
  • RNA, Small Nuclear
  • Transcription Factors
  • RNA Polymerase II

Grants and funding

JC is funded by the European Refbio II program (EFA038_Momeneu) (refbio.eu/en/), Instituto de Estudios Riojanos (I.E.R.) and by the Rioja Salud Foundation (www.fundacionriojasalud.org). HN is funded by the South East Norway Regional Health Authority (grant No. 2015029). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.