U2 snRNP is required for expression of the 3' end of genes

Mitsunori Koga; Takayuki Satoh; Ichiro Takasaki; Yumi Kawamura; Minoru Yoshida; Daisuke Kaida

doi:10.1371/journal.pone.0098015

U2 snRNP is required for expression of the 3' end of genes

PLoS One. 2014 May 20;9(5):e98015. doi: 10.1371/journal.pone.0098015. eCollection 2014.

Authors

Mitsunori Koga¹, Takayuki Satoh¹, Ichiro Takasaki², Yumi Kawamura³, Minoru Yoshida⁴, Daisuke Kaida¹

Affiliations

¹ Frontier Research Core for Life Sciences, University of Toyama, Toyama, Japan.
² Division of Molecular Genetics Research, Life Science Research Center, University of Toyama, Toyama, Japan.
³ Molecular Ligand Target Research Team, RIKEN Center for Sustainable Resource Science, Wako, Saitama, Japan.
⁴ Chemical Genetics Laboratory, RIKEN, Wako, Saitama, Japan; JST, CREST, Kawaguchi, Saitama, Japan.

Abstract

Pre-mRNA in eukaryotes is subjected to mRNA processing, which includes capping, polyadenylation, and splicing. Transcription and mRNA processing are coupled, and this coupling stimulates mRNA processing; however, the effects of mRNA processing on transcription are not fully understood. In this study, we found that inhibition of U2 snRNP by a splicing inhibitor, spliceostatin A (SSA), or by an antisense oligonucleotide to U2 snRNA, caused gene-specific 3'-end down-regulation. Removal of SSA from the culture media restored expression of the 3' ends of genes, suggesting that U2 snRNP is required for expression of the 3' end of genes. Finally, we found that SSA treatment caused accumulation of Pol II near the 5' end of 3'-end down regulated genes, such as CDK6, SMEK2 and EGFR, indicating that SSA treatment led to transcription elongation arrest on these genes. These findings suggest that U2 snRNP is important for production of full length mRNA probably through regulation of transcription elongation, and that a novel checkpoint mechanism prevents pre-mRNA from accumulating as a result of splicing deficiencies, and thereby prevents production of aberrant proteins that might be translated from pre-mRNAs through the arrest of transcription elongation.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

3' Untranslated Regions*
5' Untranslated Regions
Cell Line
Exosome Multienzyme Ribonuclease Complex / genetics
Gene Expression Regulation* / drug effects
Gene Knockdown Techniques
HeLa Cells
Humans
Pyrans / pharmacology
RNA Polymerase II / metabolism
RNA Precursors / genetics
RNA Splicing / drug effects
RNA, Messenger / genetics
RNA-Binding Proteins / genetics
Ribonucleoprotein, U2 Small Nuclear / metabolism*
Spiro Compounds / pharmacology
Transcription, Genetic

Substances

3' Untranslated Regions
5' Untranslated Regions
EXOSC2 protein, human
Pyrans
RNA Precursors
RNA, Messenger
RNA-Binding Proteins
Ribonucleoprotein, U2 Small Nuclear
Spiro Compounds
spliceostatin A
RNA Polymerase II
Exosome Multienzyme Ribonuclease Complex

Grants and funding

This work was supported in part by the Program to Disseminate Tenure Tracking System, JST, and Grants-in-Aid from JSPS (23870010, 25711001), the Sumitomo Foundation, Takeda Science Foundation, Mochida Memorial Foundation for Medical and Pharmaceutical Research, The Sagawa Foundation for Promotion of Cancer Research, Kowa Life Science Foundation and Human Frontier Science Program (RGY0080/2013). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.