Related Experiment Video
Updated: Nov 29, 2025
08:25
Identification of Circular RNAs using RNA Sequencing
Published on: November 14, 2019
12.6K
SRRM4 Expands the Repertoire of Circular RNAs by Regulating Microexon Inclusion
Vanessa M Conn1,2, Marta Gabryelska1,2, Shashikanth Marri1,2
1Flinders Cancer Research, College of Medicine and Public Health, Flinders University, Bedford Park 5042, South Australia, Australia.
Cells
|November 19, 2020
Summary
Researchers discovered over 100,000 circular RNAs (circRNAs), including previously overlooked microexons (MEs). The splicing factor SRRM4 drives the biogenesis of novel microexon-containing circRNAs (ME-circRNAs), impacting cancer prognostics.
Area of Science:
- Non-coding RNA biology
- Bioinformatics
- Cancer genomics
Background:
- High-throughput RNA sequencing (RNA-seq) has identified over 100,000 circular RNAs (circRNAs).
- Microexons (MEs), present in 30% of mRNA transcripts, have been largely overlooked in circRNA research.
- circRNAs show potential as prognostic markers in gliomas.
Purpose of the Study:
- To identify and characterize microexon-containing circRNAs (ME-circRNAs).
- To investigate the role of the splicing factor SRRM4 in ME-circRNA biogenesis.
- To explore the clinical relevance of ME-circRNAs in glioma.
Main Methods:
- Utilized standard circRNA prediction pipelines (CIRCexplorer2, CIRI2) and a novel chimera-identification pipeline (Hyb).
- Analyzed circRNA-seq datasets from glioma tissues and matched controls.
- Overexpressed SRRM4 in HEK293 cells to study ME-circRNA generation.
Main Results:
- Identified over 2000 ME-circRNAs containing novel MEs previously uncalled by standard pipelines.
- ME-circRNA abundance in gliomas correlated with SRRM4 expression.
- SRRM4 overexpression induced over 2000 novel ME-circRNAs, including ME-circEIF4G3, and altered canonical circRNA levels.
Conclusions:
- SRRM4 is a bona fide circRNA biogenesis factor, particularly for ME-circRNAs.
- ME-circRNAs represent a newly recognized class of non-coding RNAs with implications in oncogenesis.
- ME-circRNAs and SRRM4 hold potential as prognostic biomarkers for glioma stratification.
Related Concept Videos
02:53Ribosomal RNA Synthesis
14.2K
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
14.2K
02:53Ribosomal RNA Synthesis
3.9K
3.9K
02:18Alternative RNA Splicing
23.9K
Alternative RNA splicing is the regulated splicing of exons and introns to produce different mature mRNAs from a single pre-mRNA. Unlike in constitutive splicing where a single gene produces a single type of mRNA, alternative splicing allows an organism to produce multiple proteins from a single gene and plays an important role in protein diversity.
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...
23.9K
02:18Alternative RNA Splicing
4.5K
4.5K
01:32RNA Splicing
59.5K
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
59.5K
01:29Translational Regulation
391
Translational regulation in prokaryotes ensures efficient protein synthesis by controlling ribosome access to mRNA. This regulation is mediated by secondary RNA structures, including translational riboswitches, RNA thermometers, and small RNAs (sRNAs), which respond to intracellular and environmental signals to modulate gene expression.Translational RiboswitchesRiboswitches in the leader region of mRNAs can regulate translation by altering the accessibility of the Shine-Dalgarno (SD) sequence,...
391