Related Experiment Video
Updated: Jan 25, 2026
07:08
Fully Processed Recombinant KRAS4b: Isolating and Characterizing the Farnesylated and Methylated Protein
Published on: January 16, 2020
6.1K
METTL1 Promotes let-7 MicroRNA Processing via m7G Methylation
Luca Pandolfini1, Isaia Barbieri2, Andrew J Bannister1
1The Gurdon Institute and Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK.
Molecular Cell
|April 30, 2019
Summary
Researchers discovered a new RNA modification pathway involving 7-methylguanosine (m7G) in microRNAs (miRNAs). This METTL1-dependent methylation impacts miRNA processing and regulates cell migration.
Area of Science:
- Molecular Biology
- Epigenetics
- RNA Biology
Background:
- 7-methylguanosine (m7G) is a known RNA modification found in mRNA caps, tRNAs, and rRNAs.
- Detecting internal m7G in low-abundance RNAs like microRNAs (miRNAs) has been challenging due to a lack of sensitive methods.
Purpose of the Study:
- To develop a sensitive method for detecting internal m7G in miRNAs.
- To investigate the role of m7G modification in miRNA function and regulation of cell migration.
Main Methods:
- Adaptation of a chemical reactivity assay for sensitive detection of internal m7G in miRNAs.
- Borohydride Reduction sequencing (BoRed-seq) combined with RNA immunoprecipitation.
- Mass spectrometry for precise mapping of m7G modifications.
Main Results:
- Identification of m7G within a subset of miRNAs that inhibit cell migration.
- Demonstration that METTL1 methyltransferase mediates m7G methylation in miRNAs.
- Mapping of m7G to a specific guanosine in let-7e-5p miRNA, revealing METTL1's role in regulating miRNA processing and cell migration.
Conclusions:
- METTL1-dependent N7-methylation of guanosine represents a novel RNA modification pathway.
- This pathway regulates miRNA structure, biogenesis, and consequently, cell migration.
Related Concept Videos
01:22MicroRNAs
24.1K
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...
24.1K
01:22MicroRNAs
3.9K
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...
3.9K
02:40The Eukaryotic Promoter Region
18.7K
The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...
18.7K
02:40The Eukaryotic Promoter Region
3.8K
3.8K
00:50Anaphase Promoting Complex
3.3K
The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...
3.3K
01:17Phase II Reactions: Methylation Reactions
697
Methylation is a phase II biotransformation process involving the attachment of a methyl group to a substrate. Enzymes known as methyltransferases orchestrate this reaction.
The mechanism of methylation unfolds in two stages. The first stage sees a methyltransferase enzyme facilitating the transfer of a methyl group from S-adenosylmethionine (SAM) to the substrate, forming S-adenosylhomocysteine (SAH). The second stage involves further metabolism of SAH into homocysteine, which can be recycled...
The mechanism of methylation unfolds in two stages. The first stage sees a methyltransferase enzyme facilitating the transfer of a methyl group from S-adenosylmethionine (SAM) to the substrate, forming S-adenosylhomocysteine (SAH). The second stage involves further metabolism of SAH into homocysteine, which can be recycled...
697