Related Experiment Video

Updated: Jun 9, 2025

A Complete Pipeline for Isolating and Sequencing MicroRNAs, and Analyzing Them Using Open Source Tools
00:09

A Complete Pipeline for Isolating and Sequencing MicroRNAs, and Analyzing Them Using Open Source Tools

Published on: August 21, 2019

7.3K

Effects of METTL3-METTL14 on primary microRNA processing by Drosha-DGCR8

Brijesh Khadgi, Yunsun Nam

    Biorxiv : the Preprint Server for Biology
    |October 28, 2024
    PubMed

    Insights

    N6-methyladenosine (m6A) modification and METTL3-METTL14 do not generally enhance microRNA processing by the Microprocessor complex. This study challenges previous models by showing no direct impact on Drosha-DGCR8 function or m6A-modified pri-miRNAs.

    Area of Science:

    • Molecular Biology
    • RNA Biology
    • Gene Regulation

    Background:

    • MicroRNAs (miRNAs) are crucial regulators of gene expression, with their maturation involving the Microprocessor complex (Drosha-DGCR8).
    • Chemical modifications, such as N6-methyladenosine (m6A), on primary miRNA transcripts (pri-miRNAs) are proposed to influence Microprocessor processing efficiency.
    • The methyltransferase complex METTL3-METTL14 is known to produce m6A modifications on RNA molecules.

    Purpose of the Study:

    • To investigate whether METTL3-METTL14 or m6A modification directly impacts the function of Drosha-DGCR8 in pri-miRNA processing.
    • To elucidate the molecular mechanism by which METTL3-METTL14 might affect pri-miRNA maturation.

    Main Methods:

    • Reconstitution assays using purified METTL3-METTL14 methyltransferase complex and Drosha-DGCR8 Microprocessor complex.
    • Biochemical assays to assess the processing efficiency of pri-miRNAs with and without m6A modification.
    • Analysis of potential complex formation between METTL3-METTL14 and DGCR8.

    Main Results:

    • The presence of METTL3-METTL14 complexes did not alter the processing efficiency of Drosha-DGCR8 on pri-miRNAs.
    • pri-miRNAs modified with m6A showed similar processing rates compared to unmodified transcripts.
    • Stable complex formation between recombinant METTL3-METTL14 and DGCR8 was not observed, contradicting models of enhanced DGCR8 recruitment.

    Conclusions:

    • METTL3-METTL14 and m6A modification do not generally promote Microprocessor-mediated pri-miRNA processing.
    • The findings challenge the existing model suggesting a direct role for METTL3-METTL14 in enhancing Drosha-DGCR8 activity.
    • While not a general mechanism, specific roles in certain pri-miRNA processing events cannot be excluded.

    More Related Videos

    Identifying Targets of Human microRNAs with the LightSwitch Luciferase Assay System using 3'UTR-reporter Constructs and a microRNA Mimic in Adherent Cells07:19

    Identifying Targets of Human microRNAs with the LightSwitch Luciferase Assay System using 3'UTR-reporter Constructs and a microRNA Mimic in Adherent Cells

    Published on: September 28, 2011

    36.1K
    A Reporter Assay to Analyze Intronic microRNA Maturation in Mammalian Cells06:48

    A Reporter Assay to Analyze Intronic microRNA Maturation in Mammalian Cells

    Published on: June 16, 2022

    1.9K

    Related Concept Videos

    MicroRNAs01:22

    MicroRNAs

    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...
    3.0K
    Experimental RNAi02:15

    Experimental 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...
    6.1K
    RNA Interference01:23

    RNA 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...
    25.9K
    siRNA - Small Interfering RNAs02:30

    siRNA - Small Interfering RNAs

    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...
    16.6K
    Regulation of Expression Occurs at Multiple Steps02:24

    Regulation of Expression Occurs at Multiple Steps

    Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
    Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
    22.5K
    piRNA - Piwi-interacting RNAs02:57

    piRNA - 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...
    6.8K