Nuclear retention element recruits U1 snRNP components to restrain spliced lncRNAs in the nucleus

RNA Biol. 2019 Aug;16(8):1001-1009. doi: 10.1080/15476286.2019.1620061. Epub 2019 Jun 4.

Abstract

In contrast to cytoplasmic localization of spliced mRNAs, many spliced lncRNAs are localized in the nucleus. To investigate the mechanism, we used lncRNA MEG3 as a reporter and mapped a potent nuclear retention element (NRE), deletion of this element led to striking export of MEG3 from the nucleus to the cytoplasm. Insertion of the NRE resulted in nuclear retention of spliced lncRNA as well as spliced mRNA. We further purified RNP assembled on the NRE in vitro and identified the proteins by mass spectrometry. Screen using siRNA revealed depletion of U1 snRNP components SNRPA, SNRNP70 or SNRPD2 caused significant cytoplasmic localization of MEG3 reporter transcripts. Co-knockdown these factors in HFF1 cells resulted in an increased cytoplasmic distribution of endogenous lncRNAs. Together, these data support a model that U1 snRNP components restrain spliced lncRNAs in the nucleus via the interaction with nuclear retention element.

Keywords: LncRNA localization; MEG3; U1 snRNP components; nuclear retention element.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Nucleus / genetics
  • Cytoplasm / genetics
  • Cytosol / metabolism
  • HeLa Cells
  • Humans
  • RNA Splicing / genetics
  • RNA, Long Noncoding / genetics
  • Ribonucleoprotein, U1 Small Nuclear / chemistry
  • Ribonucleoprotein, U1 Small Nuclear / genetics*
  • Spliceosomes / genetics
  • snRNP Core Proteins / genetics*

Substances

  • MEG3 non-coding RNA, human
  • RNA, Long Noncoding
  • Ribonucleoprotein, U1 Small Nuclear
  • SNRNP70 protein, human
  • SNRPD2 protein, human
  • U1A protein
  • snRNP Core Proteins

Grants and funding

This work was sponsored by National Natural Science Foundation of China [Grants 31670823, 81472491 to H. Lei, 31701197 to S. Hou], and Liaoning Pandeng Program.