Related Experiment Video
Updated: Jun 2, 2026
11:00
Biotin-based Pulldown Assay to Validate mRNA Targets of Cellular miRNAs
Published on: June 12, 2018
Versatility of MicroRNA biogenesis.
1Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Plos One
|May 17, 2011
Summary
MicroRNA (miRNA) biogenesis is versatile, with varying precursor to mature miRNA ratios. Factors like hnRNPR and hnRNPH1 influence miRNA processing, highlighting pathway complexity.
Area of Science:
- Molecular Biology
- Genetics
- RNA Biology
Background:
- MicroRNAs (miRNAs) are key regulators of gene expression.
- MiRNA biogenesis involves complex processing of primary (pri) and precursor (pre) transcripts into mature forms.
- The uniformity of miRNA processing across different miRNAs remains unclear.
Purpose of the Study:
- To investigate the variability in miRNA biogenesis.
- To identify factors influencing the ratio of precursor miRNA (pre-miRNA) to mature miRNA.
- To explore the roles of hnRNPH1 and hnRNPR in miRNA processing.
Main Methods:
- Analysis of pre-miRNA to mature miRNA ratios across different miRNAs.
- Over-expression studies of miRNA biogenesis factors (Exportin-5, Drosha, NF90a, NF45, KSRP).
- Gene knockdown and over-expression of hnRNPH1 and hnRNPR.
Main Results:
- The ratio of pre-miRNA to mature miRNA varies significantly between different miRNAs.
- Biogenesis factors exhibited bidirectional effects on pre/mature miRNA ratios.
- hnRNPR was found to inhibit miRNA processing, while hnRNPH1 facilitates it.
Conclusions:
- MiRNA biogenesis is a versatile process with significant inter-miRNA variability.
- Specific hnRNP proteins play opposing roles in modulating miRNA processing efficiency.
- These findings contribute to understanding the intricate regulation of miRNA maturation.
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...
02:57piRNA - Piwi-interacting RNAs
PIWI-interacting RNAs, or piRNAs, are the most abundant short non-coding RNAs. More than 20,000 genes have been found in humans that code for piRNAs while only 2000 genes have been found for miRNAs. piRNAs can act at the transcriptional and post-transcriptional levels and have a vital role in silencing transposable elements present in germ cells. They are also involved in epigenetic silencing and activation. Previously, they were thought to function only in germ cells but new evidence suggests...
02:15Experimental RNAi
RNA interference (RNAi) is a cellular mechanism that inhibits gene expression by suppressing its transcription or activating the RNA degradation process. The mechanism was discovered by Andrew Fire and Craig Mello in 1998 in plants. Today, it is observed in almost all eukaryotes, including protozoa, flies, nematodes, insects, parasites, and mammals. This precise cellular mechanism of gene silencing has been developed into a technique that provides an efficient way to identify and determine the...
02:30Small interfering RNAs (siRNA)
Small interfering RNAs, or siRNAs, are short regulatory RNA molecules that can silence genes post-transcriptionally, as well as the transcriptional level in some cases. siRNAs are important for protecting cells against viral infections and silencing transposable genetic elements.
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the ATP-dependent...
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the ATP-dependent...