Related Experiment Video
Updated: Jun 24, 2026
06:48
A Reporter Assay to Analyze Intronic microRNA Maturation in Mammalian Cells
Published on: June 16, 2022
Dual function of ERH in primary miRNA biogenesis.
Simon Aschenwald1, Aswini K Panda2,3,4, Theresa Wurzer1
1Institute of Developmental Immunology, Biocenter, Medical University Innsbruck, Innsbruck 6020, Austria.
Nucleic Acids Research
|June 23, 2026
Summary
Scaffold attachment factor B2 (SAFB2) and enhancer of rudimentary homolog (ERH) are crucial for microRNA (miRNA) biogenesis. This study reveals ERH has dual roles: suppressing miRNA production via DGCR8 binding and aiding cluster assistance without DGCR8 interaction.
Area of Science:
- Molecular Biology
- Genetics
- RNA Biology
Background:
- MicroRNAs (miRNAs) are key regulators of gene expression, processed by the Microprocessor complex (DROSHA-DGCR8).
- Cluster assistance describes how a primary miRNA hairpin can facilitate the processing of a nearby suboptimal hairpin.
- SAFB2 and ERH were previously identified as factors involved in cluster assistance, interacting with DROSHA and DGCR8.
Purpose of the Study:
- To elucidate the precise roles of ERH and SAFB2 in primary miRNA (pri-miRNA) biogenesis and cluster assistance.
- To determine if protein-protein interactions between ERH, SAFB2, and DGCR8 are essential for cluster assistance.
Main Methods:
- Genetic screening and mechanistic analyses were employed.
- The study focused on the functional impact of ERH loss on the miRNA transcriptome.
- Investigated the necessity of ERH-SAFB2 and ERH-DGCR8 interactions for cluster assistance.
Main Results:
- Loss of ERH phenocopied SAFB1/2 deletion effects on the miRNA transcriptome, indicating shared roles in pri-miRNA biogenesis.
- SAFB1/2 and ERH are essential for efficient Microprocessor feedback regulation via pri-miR-1306 processing, demonstrating a physiological function for cluster assistance.
- ERH-mediated cluster assistance is independent of its direct association with SAFB2 or DGCR8.
- Disruption of the ERH binding site on DGCR8 promoted processing of non-cluster assistance pri-miRNAs.
Conclusions:
- ERH plays dual roles in pri-miRNA biogenesis: a suppressive role through DGCR8 binding and a non-DGCR8-dependent role in cluster assistance.
- The findings clarify the mechanistic basis of cluster assistance and the multifaceted function of ERH in miRNA processing.
Related Concept Videos
01:22MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...
01:22MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
01:22MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
01:23RNA Interference
RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
01:23RNA Interference
RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
01:31Regulation of the Unfolded Protein Response
Inositol-requiring kinase one or IRE1 is the most conserved eukaryotic unfolded protein response (UPR) receptor. It is a type I transmembrane protein kinase receptor with a distinctive site-specific RNase activity. As the binding mechanics of the misfolded proteins with the N-terminal domain of IRE-1 are unclear, three binding models — direct, indirect, and allosteric -- are proposed for receptor activation. Nevertheless, it is known that once a misfolded protein associates with IRE1, it...