GO:0000710 meiotic mismatch repair: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0000710 meiotic mismatch repair is the biological process that identifies and corrects base-base mismatches, small insertion-deletion loops, and regions of heterology in duplex DNA formed during meiotic recombination.
• Mismatch repair (MMR) proteins are essential for meiotic crossing over and for maintaining genome stability during meiosis.
• Defects in meiotic mismatch repair can lead to non-Mendelian segregation of alleles and are associated with infertility and cancer predisposition.
• Key genes involved include MLH1, MSH2, MSH4, MSH5, MSH6, PMS2, and others that function in MMR and meiotic recombination.
• Experimental models such as S. cerevisiae and mouse knockouts have been instrumental in dissecting the roles of MMR proteins in meiosis.
• Understanding meiotic mismatch repair has implications for reproductive biology, cancer genetics, and evolutionary studies.
Description
Meiotic mismatch repair (GO:0000710) is a specialized DNA repair process that operates during meiosis to correct mismatches and heterologies in recombination intermediates. This process ensures the fidelity of genetic exchange and is critical for proper chromosome segregation. Mismatch repair (MMR) proteins, originally identified for their role in post-replicative repair, also play essential roles in meiotic recombination, where they influence crossover formation and distribution. The importance of meiotic mismatch repair extends to human health, as deficiencies in MMR genes are linked to infertility and cancer. Research into this process has been advanced by studies in model organisms such as Saccharomyces cerevisiae and mice, which have revealed conserved mechanisms and regulatory factors. This article provides a comprehensive overview of the definition, mechanisms, key genes, and research methods associated with meiotic mismatch repair, based on authoritative QuickGO data and published literature.
meiotic mismatch repair At A Glance
| GO ID | GO:0000710 |
|---|---|
| GO term | meiotic mismatch repair |
| Ontology | biological_process |
| Synonym | none |
| Major function | Identification and correction of mismatches and heterologies in recombination intermediates during meiosis |
| Related processes | Meiotic recombination, crossing over, DNA mismatch repair |
| Key proteins | MLH1, MSH2, MSH4, MSH5, MSH6, PMS2, and others |
| Associated diseases | Infertility, cancer predisposition (e.g., Lynch syndrome) |
What Is GO:0000710?
According to the Gene Ontology, meiotic mismatch repair (GO:0000710) is defined as a system for the identification and correction of base-base mismatches, small insertion-deletion loops, and regions of heterology that are present in duplex DNA formed with strands from two recombining molecules. Correction of the mismatch can result in non-Mendelian segregation of alleles following meiosis. In simpler terms, it is the process that fixes errors in DNA that occur when chromosomes exchange genetic material during the formation of gametes, ensuring that the genetic information is accurately passed on.
Why Is meiotic mismatch repair Important in Cell Biology?
Meiotic mismatch repair is crucial for maintaining genomic integrity during meiosis, the specialized cell division that produces gametes. By correcting mismatches and heterologies in recombination intermediates, it ensures proper chromosome segregation and prevents non-Mendelian inheritance patterns. Defects in this process can lead to infertility, aneuploidy, and increased cancer risk, making it a significant area of study in reproductive biology and oncology. Furthermore, understanding meiotic mismatch repair provides insights into evolutionary mechanisms and the maintenance of genetic diversity.
• Ensures accurate chromosome segregation during meiosis, preventing aneuploidy.
• Prevents non-Mendelian segregation of alleles, which can distort inheritance patterns.
• Deficiencies in MMR genes are linked to male and female infertility.
• MMR proteins are involved in the regulation of meiotic crossing over, influencing genetic diversity.
• Mutations in MMR genes cause Lynch syndrome, a hereditary cancer predisposition.
• Meiotic mismatch repair is conserved from yeast to humans, facilitating model organism studies.
• Plays a role in speciation by suppressing recombination between divergent sequences.
• Provides targets for reproductive medicine and cancer diagnostics.
• Helps maintain genome stability across generations.
• Is a focus of research on the evolution of recombination and sex.
What Happens During meiotic mismatch repair?
Recognition of mismatches and heterologies
In simple terms: The cell detects errors in the DNA that occur when chromosomes exchange parts.
During meiosis, recombination intermediates contain mismatches and heterologies that are recognized by MMR proteins such as MSH2-MSH6 and MSH2-MSH3 complexes. These complexes scan the DNA for base-base mismatches and small insertion-deletion loops, initiating the repair process.
Excision and repair of mismatched DNA
In simple terms: The error-containing DNA segment is cut out and replaced with correct DNA.
Upon recognition, the MMR machinery recruits proteins such as MLH1-PMS2 (MutLα) to incise the newly synthesized strand and excise the mismatch. DNA polymerase then fills the gap, and ligase seals the nick, restoring the correct sequence.
Role in meiotic crossing over
In simple terms: MMR proteins help decide where chromosomes cross over, which is important for genetic diversity.
MMR proteins, particularly MSH4-MSH5, are required for the formation of crossovers during meiosis. They stabilize recombination intermediates and promote the resolution of Holliday junctions into crossovers, ensuring proper chromosome segregation.
Interaction with synaptonemal complex
In simple terms: MMR proteins work together with a structure that holds chromosomes together during meiosis.
The synaptonemal complex (SC) is a proteinaceous structure that mediates chromosome synapsis. Recent studies have shown that SC components interact with MMR proteins to facilitate meiotic mismatch repair and crossover formation.
Consequences of defective meiotic mismatch repair
In simple terms: If this repair process fails, it can lead to infertility and genetic disorders.
Defects in meiotic MMR can result in non-Mendelian segregation, aneuploidy, and reduced fertility. In humans, mutations in MMR genes such as MLH1 and MSH2 are associated with infertility and cancer predisposition.
Key Genes Involved in GO:0000710 meiotic mismatch repair
The following genes encode proteins that are directly involved in meiotic mismatch repair, as supported by published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| MLH1 | Forms MutLα complex with PMS2; essential for MMR and meiotic crossing over | Mutations cause Lynch syndrome and are linked to infertility |
| MSH2 | Forms MutSα and MutSβ complexes; recognizes mismatches | Defects lead to cancer predisposition and meiotic defects |
| MSH4 | Meiosis-specific MutS homolog; required for crossing over | Knockout causes meiotic arrest and infertility |
| MSH5 | Forms complex with MSH4; stabilizes recombination intermediates | Essential for crossover formation; knockout leads to sterility |
| MSH6 | Part of MutSα; recognizes base-base mismatches | Mutations associated with atypical Lynch syndrome |
| PMS2 | Part of MutLα; involved in excision and repair | Defects cause MMR deficiency and cancer risk |
| MLH3 | Forms MutLγ with MLH1; involved in crossover resolution | Required for meiotic crossing over in mice and yeast |
| EXO1 | Exonuclease involved in MMR excision | Facilitates mismatch excision during meiosis |
| RPA | Single-stranded DNA-binding protein; stabilizes intermediates | Supports MMR and recombination |
| PCNA | Sliding clamp; coordinates MMR and DNA synthesis | Essential for MMR in meiosis |
| RFC | Clamp loader; loads PCNA | Required for MMR |
| DNA polymerase delta | Synthesizes DNA during MMR | Fills gaps after excision |
| DNA ligase I | Seals nicks after repair synthesis | Finalizes MMR |
| BLM | Helicase; resolves recombination intermediates | Interacts with MMR proteins in meiosis |
| SYCP1 | Synaptonemal complex protein | Interacts with MMR machinery |
| SYCP3 | Synaptonemal complex protein | Required for synapsis and MMR |
| HOP2 | Meiosis-specific recombination protein | Facilitates strand invasion with MMR proteins |
| MND1 | Partners with HOP2 | Stabilizes recombination intermediates |
How Is meiotic mismatch repair Regulated?
Meiotic mismatch repair is regulated at multiple levels, including transcriptional control of MMR genes during meiosis, post-translational modifications of MMR proteins, and interactions with cell cycle machinery. For example, the expression of MSH4 and MSH5 is induced during meiotic prophase, and their activity is modulated by phosphorylation. Additionally, the synaptonemal complex and other meiotic structures coordinate the timing and location of MMR to ensure proper crossover formation.
meiotic mismatch repair and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| MLH1 | Lynch syndrome, infertility | Knockout mouse, human cell lines |
| MSH2 | Lynch syndrome, cancer predisposition | Conditional knockout mouse |
| MSH4 | Infertility, meiotic arrest | Knockout mouse, S. cerevisiae |
| MSH5 | Infertility, meiotic defects | Knockout mouse, yeast |
| PMS2 | Lynch syndrome, MMR deficiency | Knockout mouse, cell lines |
Meiotic mismatch repair and infertility
Defects in meiotic mismatch repair are associated with infertility in both males and females. Studies in mouse models have shown that knockout of MMR genes such as Msh4 and Msh5 leads to meiotic arrest and sterility. In humans, polymorphisms in MMR genes have been linked to impaired spermatogenesis and recurrent pregnancy loss.
Meiotic mismatch repair and cancer predisposition
Mutations in MMR genes cause Lynch syndrome, a hereditary condition that increases the risk of colorectal and other cancers. While the role of MMR in cancer is primarily through post-replicative repair, meiotic MMR defects may also contribute to genomic instability in germ cells, potentially affecting offspring.
Meiotic mismatch repair in evolutionary biology
Meiotic mismatch repair suppresses recombination between divergent sequences, contributing to reproductive isolation and speciation. Studies in parthenogenetic lizards have shown that MMR proteins are involved in meiotic synapsis of homeologous chromosomes, highlighting their role in evolution.
From meiotic mismatch repair-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does knockout of Msh4 cause meiotic arrest? | Msh4 knockout mouse |
| How does a point mutation in MLH1 affect MMR activity? | Point-mutation knock-in cell line |
| Can overexpression of MSH6 rescue MMR deficiency? | Overexpression cell model |
| Where is MSH5 localized during meiosis? | Tagged knock-in mouse (e.g., GFP-MSH5) |
| What is the effect of a cancer-associated MSH2 variant on meiosis? | Knock-in mouse model |
| How does synaptonemal complex loss affect MMR? | Sycp3 knockout mouse |
How to Study the meiotic mismatch repair Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Tetrad dissection | Spore viability and recombination frequency | Yeast meiotic MMR studies |
| Immunofluorescence | MLH1 foci formation | Mouse spermatocyte crossover analysis |
| ChIP-seq | MMR protein binding sites | Mapping recombination hotspots |
| In vitro MMR assay | Repair efficiency of mismatched DNA | Biochemical characterization of MMR mutants |
| Sperm typing | Recombination and non-Mendelian segregation | Human population studies |
| CRISPR knockout | Gene function in meiosis | Generating MMR-deficient cell lines |
| Live-cell imaging | Dynamic localization of MMR proteins | Tracking repair in real time |
| RNA-seq | Expression of MMR genes during meiosis | Transcriptional profiling |
Genetic approaches in model organisms
Yeast and mouse models are widely used to study meiotic mismatch repair. Knockout strains for MMR genes (e.g., msh4Δ, msh5Δ) display meiotic defects that can be analyzed by tetrad dissection, spore viability, and recombination frequency assays. Mouse knockouts provide insights into mammalian-specific aspects and infertility phenotypes.
Cytological and imaging techniques
Immunofluorescence and electron microscopy can visualize MMR proteins and synaptonemal complex components on meiotic chromosomes. For example, staining for MLH1 foci is a standard method to assess crossing over in mouse spermatocytes. Live-cell imaging of tagged MMR proteins allows dynamic tracking of repair events.
Biochemical and molecular assays
In vitro mismatch repair assays using cell extracts or purified proteins can measure repair efficiency and identify defects in specific mutants. Chromatin immunoprecipitation (ChIP) and DNA sequencing can map MMR protein binding sites and recombination hotspots.
Genomic and bioinformatic analyses
Next-generation sequencing of meiotic products (e.g., sperm typing) can detect non-Mendelian segregation and recombination patterns. Bioinformatics tools analyze crossover distribution and identify MMR gene variants in patient cohorts.
How CRISPR Can Be Used to Study GO:0000710 meiotic mismatch repair
Knockout
CRISPR knockout of MMR genes such as MLH1, MSH2, or MSH4 in cell lines or model organisms can reveal their essential roles in meiotic mismatch repair. For example, MSH4 knockout mice exhibit meiotic arrest and infertility, providing a model for studying human reproductive disorders.
Point Mutation
Introducing point mutations associated with human diseases (e.g., MLH1 variants found in Lynch syndrome) into cell lines or mice allows functional assessment of MMR activity and meiotic phenotypes. This approach helps distinguish pathogenic from benign variants.
Knock-in
Knock-in of tagged versions of MMR proteins (e.g., GFP-MSH5) enables live-cell imaging and localization studies during meiosis. This provides insights into the dynamic assembly of MMR complexes on meiotic chromosomes.
Overexpression
Overexpression of MMR genes can test whether increased dosage affects meiotic recombination or rescues defects in heterozygous mutants. For example, overexpressing MSH6 in MMR-deficient cells can restore mismatch repair activity.
How EDITGENE Supports meiotic mismatch repair Research
Researchers studying meiotic mismatch repair-related genes often need to determine whether a candidate gene is causally involved in the process or contributes to disease. EDITGENE provides comprehensive CRISPR-based services to generate precisely engineered cell and animal models, enabling functional studies of MMR genes in meiosis and beyond.
Contact EDITGENE today to design your custom CRISPR model for meiotic mismatch repair research.
Frequently Asked Questions About meiotic mismatch repair
What is meiotic mismatch repair?
Meiotic mismatch repair (GO:0000710) is a biological process that corrects mismatches and heterologies in DNA during meiosis, ensuring accurate chromosome segregation and genetic stability.
What genes are involved in meiotic mismatch repair?
Key genes include MLH1, MSH2, MSH4, MSH5, MSH6, PMS2, and others that encode proteins functioning in mismatch recognition and repair.
Why is meiotic mismatch repair important?
It prevents non-Mendelian segregation, aneuploidy, and infertility, and defects are linked to cancer predisposition.
How does meiotic mismatch repair relate to cancer?
Mutations in MMR genes cause Lynch syndrome and increase cancer risk; meiotic defects may also affect germ cell stability.
What model organisms are used to study meiotic mismatch repair?
Saccharomyces cerevisiae and mice are commonly used due to conserved mechanisms and available genetic tools.
What are the consequences of defective meiotic mismatch repair?
Defects can lead to meiotic arrest, sterility, and increased mutation rates in offspring.
How can CRISPR be used to study meiotic mismatch repair?
CRISPR enables knockout, point mutation knock-in, and tagging of MMR genes in cell lines and animal models to dissect their functions.
What methods are used to analyze meiotic mismatch repair?
Methods include tetrad dissection, immunofluorescence, ChIP-seq, in vitro repair assays, and sperm typing.
Is meiotic mismatch repair conserved across species?
Yes, core MMR proteins and mechanisms are conserved from yeast to humans.
What diseases are associated with meiotic mismatch repair defects?
Infertility, Lynch syndrome, and other cancers are associated with MMR gene mutations.
Conclusion
Meiotic mismatch repair (GO:0000710) is a fundamental biological process that safeguards genetic integrity during meiosis. Its mechanisms, involving a suite of MMR proteins, are critical for proper recombination and chromosome segregation. Dysregulation of this process leads to infertility and cancer, underscoring its clinical relevance. Continued research using advanced CRISPR models and genomic tools will further illuminate the intricate roles of MMR in meiosis and human disease.
References
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- 3. Hoffmann ER et al.. 2004. Meiotic recombination intermediates and mismatch repair proteins.. Cytogenet Genome Res 107(3-4):232-48 PMID: 15467368
- 4. Harper JA et al.. 2025. Mismatch repair disturbs meiotic crossover control in S. cerevisiae.. Nucleic Acids Res 53(21) PMID: 41242522
- 5. Voelkel-Meiman K et al.. 2022. A role for synaptonemal complex in meiotic mismatch repair.. Genetics 220(2) PMID: 35100397
- 6. Buermeyer AB et al.. 1999. Mammalian DNA mismatch repair.. Annu Rev Genet 33:533-64 PMID: 10690417
- 7. Spangenberg V et al.. 2021. Meiotic synapsis of homeologous chromosomes and mismatch repair protein detection in the parthenogenetic rock lizard Darevskia unisexualis.. Mol Reprod Dev 88(2):119-127 PMID: 33438277
- 8. Mukherjee S et al.. 2010. DNA mismatch repair and infertility.. Curr Opin Urol 20(6):525-32 PMID: 20852424
