GO:0070877 microprocessor complex: Components, Assembly and Research Methods, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0070877 microprocessor complex is a cellular component that binds heme and pri-miRNAs and is required for pre-miRNA formation, the initial step of miRNA biogenesis.
• The complex is composed of the double-stranded-RNA-specific RNase Drosha (RNASEN) and the RNA-binding protein DGCR8, which acts as a molecular anchor to recognize pri-miRNA at dsRNA-ssRNA junctions.
• DGCR8 directs Drosha to cleave the 3' and 5' strands of a stem-loop to release hairpin-shaped pre-miRNAs.
• The microprocessor complex is regulated by post-translational modifications, including SUMOylation of DGCR8 by USP36, which affects miRNA biogenesis.
• In plants, chromatin-associated microprocessor assembly is regulated by the U1 snRNP auxiliary protein PRP40.
• Research methods for studying the microprocessor complex include pri-miRNA cleavage assays, RNA-seq, proteomics, and CRISPR-based models [1,2,4].
Description
The microprocessor complex (GO:0070877) is a cellular component that binds heme and pri-miRNAs and is required for the formation of pre-miRNA, the initial step of microRNA (miRNA) biogenesis. This complex is composed of the double-stranded-RNA-specific RNase Drosha (also called RNASEN) and the RNA-binding protein DGCR8 (heme-free or heme-bound forms). Within the complex, DGCR8 functions as a molecular anchor necessary for the recognition of pri-miRNA at dsRNA-ssRNA junctions and directs RNASEN/Drosha to cleave the 3' and 5' strands of a stem-loop to release hairpin-shaped pre-miRNAs. Understanding the microprocessor complex is fundamental for researchers studying miRNA biogenesis, gene regulation, and related diseases. The complex is highly conserved and its dysfunction has been linked to various pathological conditions [2,4].
microprocessor complex At A Glance
| GO ID | GO:0070877 |
|---|---|
| GO term | microprocessor complex |
| Ontology | cellular_component |
| Synonym | none |
| Major function | Binds heme and pri-miRNAs; required for pre-miRNA formation in miRNA biogenesis |
| Components | Drosha (RNASEN) and DGCR8 |
| Substrate | pri-miRNA |
| Product | pre-miRNA |
| Regulation | SUMOylation of DGCR8 by USP36; chromatin-associated assembly regulated by PRP40 in plants |
What Is GO:0070877?
The microprocessor complex is a protein complex that binds heme and pri-miRNAs and is essential for the formation of pre-miRNA, the initial step of miRNA biogenesis. It consists of the RNase Drosha and the RNA-binding protein DGCR8. DGCR8 recognizes pri-miRNA at dsRNA-ssRNA junctions and directs Drosha to cleave the stem-loop, releasing pre-miRNAs.
Why Is microprocessor complex Important in Cell Biology?
The microprocessor complex is crucial for miRNA biogenesis, which regulates gene expression at the post-transcriptional level. Dysregulation of miRNA biogenesis is associated with cancer, neurological disorders, and developmental defects [2,4]. Studying this complex provides insights into fundamental RNA processing mechanisms and potential therapeutic targets.
• Essential for miRNA biogenesis and gene silencing.
• Drosha and DGCR8 are core components; mutations affect miRNA profiles.
• Regulated by SUMOylation via USP36, linking to cancer pathways.
• Chromatin-associated assembly in plants involves PRP40.
• Dysregulation contributes to cancer and other diseases.
• Target for CRISPR-based knockout and knock-in studies [1,2,4].
• Involved in stem cell pluripotency and differentiation.
• Potential therapeutic target for miRNA-related disorders.
What Happens During microprocessor complex?
Pri-miRNA Recognition
In simple terms: The microprocessor complex finds and binds to primary microRNA transcripts.
DGCR8, a double-stranded RNA-binding protein, recognizes the junction between double-stranded and single-stranded RNA regions in pri-miRNAs, acting as a molecular anchor.
Cleavage of Pri-miRNA
In simple terms: Drosha cuts the pri-miRNA to release a hairpin-shaped pre-miRNA.
The RNase Drosha, guided by DGCR8, cleaves the 3' and 5' strands of the stem-loop structure, releasing the pre-miRNA.
Heme Binding and Regulation
In simple terms: Heme binding to DGCR8 modulates the complex activity.
The microprocessor complex binds heme; heme-free or heme-bound forms of DGCR8 exist, and heme binding may regulate pri-miRNA processing.
Post-translational Modifications
In simple terms: Chemical modifications like SUMOylation control the complex.
USP36 associates with the microprocessor complex and SUMOylates DGCR8, regulating miRNA biogenesis.
Chromatin Association in Plants
In simple terms: In plants, the complex assembles on chromatin with help from PRP40.
The U1 snRNP auxiliary protein PRP40 regulates chromatin-associated microprocessor assembly in plants.
Key Genes Involved in GO:0070877 microprocessor complex
Key genes and proteins involved in the microprocessor complex include core components and regulators.
| Gene | Major Role | Research Relevance |
|---|---|---|
| DROSHA | RNase III enzyme that cleaves pri-miRNA | Core component; knockout reduces miRNA levels |
| DGCR8 | RNA-binding protein that anchors pri-miRNA | Core component; heme-binding; SUMOylation target [1,2] |
| USP36 | Ubiquitin-specific protease that SUMOylates DGCR8 | Regulator of miRNA biogenesis |
| PRP40 | U1 snRNP auxiliary protein | Regulates chromatin-associated microprocessor assembly in plants |
| RNASEN | Alternative name for Drosha | Same as DROSHA |
| XPO5 | Exportin-5, exports pre-miRNA | Downstream of microprocessor |
| DICER1 | Cleaves pre-miRNA to mature miRNA | Downstream effector |
| AGO2 | Argonaute protein in RISC | Effector of miRNA silencing |
| DGCR8 | Heme-free and heme-bound forms | Heme binding modulates activity |
| USP36 | SUMOylation of DGCR8 | Links to cancer pathways |
| PRP40 | Plant-specific regulator | Chromatin association |
| DROSHA | Cleaves 3' and 5' strands | Mechanistic studies |
| DGCR8 | Recognizes dsRNA-ssRNA junction | Structural studies |
| USP36 | Deubiquitinase | Regulates DGCR8 stability |
| PRP40 | U1 snRNP component | Splicing and miRNA crosstalk |
| DROSHA | Nuclear localization | Regulation of miRNA biogenesis |
| DGCR8 | Heme binding | Redox regulation |
How Is microprocessor complex Regulated?
The microprocessor complex is regulated by post-translational modifications such as SUMOylation of DGCR8 by USP36, which affects miRNA biogenesis. In plants, chromatin-associated assembly is regulated by PRP40. Heme binding to DGCR8 may also modulate activity.
microprocessor complex and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| DGCR8 | DiGeorge syndrome | Knockout mouse |
| USP36 | Cancer | Overexpression cell line |
| DROSHA | Cancer | Knockout cell line |
| PRP40 | Plant development | Arabidopsis mutant |
Cancer
Dysregulation of the microprocessor complex and its regulators, such as USP36, is implicated in cancer through altered miRNA biogenesis.
Neurodevelopmental Disorders
Mutations in DGCR8 are associated with DiGeorge syndrome, a neurodevelopmental disorder.
Plant Development
In plants, PRP40-mediated microprocessor assembly affects development and stress responses.
From microprocessor complex-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Effect of DGCR8 knockout on miRNA levels | CRISPR knockout cell line |
| Role of USP36-mediated SUMOylation | Point mutation of DGCR8 SUMO sites |
| Heme binding to DGCR8 | Knock-in of heme-binding mutants |
| Chromatin association in plants | PRP40 knockout Arabidopsis |
| Pri-miRNA cleavage activity | In vitro cleavage assay |
| miRNA target identification | RNA-seq after knockout |
How to Study the microprocessor complex Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Pri-miRNA cleavage assay | Cleavage activity | In vitro |
| RNA-seq | miRNA and mRNA expression | Knockout studies |
| Proteomics | Protein interactions | USP36 identification |
| ChIP-seq | Chromatin binding | Plant microprocessor |
| CRISPR knockout | Gene function | DROSHA/DGCR8 |
| Point mutation | Specific residue function | SUMOylation sites |
| Knock-in | Tagged proteins | Localization |
| Overexpression | Gain-of-function | USP36 |
Pri-miRNA Cleavage Assays
In vitro assays using recombinant Drosha and DGCR8 measure cleavage of pri-miRNA to pre-miRNA.
RNA Sequencing
RNA-seq quantifies miRNA and mRNA changes after microprocessor perturbation.
Proteomics
Affinity purification coupled to mass spectrometry identifies interacting proteins like USP36.
Imaging
Fluorescence microscopy visualizes nuclear localization and chromatin association.
How CRISPR Can Be Used to Study GO:0070877 microprocessor complex
Knockout
CRISPR knockout of DROSHA or DGCR8 abolishes microprocessor activity and reduces miRNA levels.
Point Mutation
Point mutations in DGCR8 SUMOylation sites reveal regulation by USP36.
Knock-in
Knock-in of tagged DGCR8 allows visualization and interaction studies.
Overexpression
Overexpression of USP36 increases DGCR8 SUMOylation and alters miRNA profiles.
How EDITGENE Supports microprocessor complex Research
Researchers studying microprocessor complex-related genes often need to determine whether a candidate gene is causally involved in miRNA biogenesis and disease. EDITGENE provides CRISPR-based services to create precise cellular models for such investigations.
Contact EDITGENE today to design your custom CRISPR model for microprocessor complex research.
Frequently Asked Questions About microprocessor complex
What is the microprocessor complex?
The microprocessor complex is a protein complex that binds heme and pri-miRNAs and is required for pre-miRNA formation in miRNA biogenesis.
What genes are involved in the microprocessor complex?
Core genes include DROSHA and DGCR8; regulators include USP36 and PRP40 [1,2,4].
What is the function of DGCR8 in the microprocessor complex?
DGCR8 acts as a molecular anchor to recognize pri-miRNA and direct Drosha cleavage.
How is the microprocessor complex regulated?
It is regulated by SUMOylation of DGCR8 by USP36 and by PRP40 in plants [2,4].
What diseases are associated with the microprocessor complex?
Cancer and DiGeorge syndrome are linked to microprocessor dysfunction [1,2].
What methods are used to study the microprocessor complex?
Pri-miRNA cleavage assays, RNA-seq, proteomics, and CRISPR models [1,2,4].
What is the GO ID for microprocessor complex?
GO:0070877.
What is the role of heme in the microprocessor complex?
Heme binds to DGCR8 and may modulate complex activity.
How does USP36 affect miRNA biogenesis?
USP36 SUMOylates DGCR8 and regulates miRNA biogenesis.
What is the plant homolog of the microprocessor complex?
In plants, PRP40 regulates chromatin-associated microprocessor assembly.
Conclusion
The microprocessor complex (GO:0070877) is a central player in miRNA biogenesis, with core components Drosha and DGCR8 and regulators like USP36 and PRP40. Understanding its structure, function, and regulation is essential for insights into gene expression and disease. CRISPR-based models from EDITGENE enable precise functional studies.
References
- 1. Le TN et al.. 2023. Pri-miRNA cleavage assays for the Microprocessor complex.. Methods Enzymol 692:217-230 PMID: 37925180
- 2. Li Y et al.. 2023. The Ubiquitin-specific Protease USP36 Associates with the Microprocessor Complex and Regulates miRNA Biogenesis by SUMOylating DGCR8.. Cancer Res Commun 3(3):459-470 PMID: 36950067
- 4. Stepien A et al.. 2022. Chromatin-associated microprocessor assembly is regulated by the U1 snRNP auxiliary protein PRP40.. Plant Cell 34(12):4920-4935 PMID: 36087009
