RNF8 - Gene
<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">RNF8 - Gene</th>
</tr>
<tr>
<td class="label">Gene Symbol</td>
<td>RNF8</td>
</tr>
<tr>
<td class="label">Gene Name</td>
<td>Ring Finger Protein 8</td>
</tr>
<tr>
<td class="label">Chromosome</td>
<td>6p21.1</td>
</tr>
<tr>
<td class="label">NCBI Gene ID</td>
<td>[9027](https://www.ncbi.nlm.nih.gov/gene/9027)</td>
</tr>
<tr>
<td class="label">OMIM ID</td>
<td>[611685](https://www.omim.org/entry/611685)</td>
</tr>
<tr>
<td class="label">Ensembl ID</td>
<td>[ENSG00000137243](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000137243)</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>[Q9UPW4](https://www.uniprot.org/uniprotkb/Q9UPW4/entry)</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td>DNA Repair Disorders, Cancer Predisposition, Neurodevelopmental Disorders, Neurodegeneration</td>
</tr>
<tr>
<td class="label">Categories</td>
<td>[DNA Repair](/mechanisms/dna-repair), [Genome Stability](/mechanisms/genome-stability), [Ubiquitin-Proteasome System](/cell-types/ubiquitin-proteasome-system)</td>
</tr>
</table>
.infobox .infobox-gene
RNF8
Overview
...RNF8 - Gene
<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">RNF8 - Gene</th>
</tr>
<tr>
<td class="label">Gene Symbol</td>
<td>RNF8</td>
</tr>
<tr>
<td class="label">Gene Name</td>
<td>Ring Finger Protein 8</td>
</tr>
<tr>
<td class="label">Chromosome</td>
<td>6p21.1</td>
</tr>
<tr>
<td class="label">NCBI Gene ID</td>
<td>[9027](https://www.ncbi.nlm.nih.gov/gene/9027)</td>
</tr>
<tr>
<td class="label">OMIM ID</td>
<td>[611685](https://www.omim.org/entry/611685)</td>
</tr>
<tr>
<td class="label">Ensembl ID</td>
<td>[ENSG00000137243](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000137243)</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>[Q9UPW4](https://www.uniprot.org/uniprotkb/Q9UPW4/entry)</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td>DNA Repair Disorders, Cancer Predisposition, Neurodevelopmental Disorders, Neurodegeneration</td>
</tr>
<tr>
<td class="label">Categories</td>
<td>[DNA Repair](/mechanisms/dna-repair), [Genome Stability](/mechanisms/genome-stability), [Ubiquitin-Proteasome System](/cell-types/ubiquitin-proteasome-system)</td>
</tr>
</table>
.infobox .infobox-gene
RNF8
Overview
Mermaid diagram (expand to render)
[RNF8](/genes/rnf8) (Ring Finger Protein 8) is an E3 ubiquitin ligase that plays a critical role in the cellular response to DNA double-strand breaks. Together with its partner RNF168, RNF8 initiates the ubiquitination cascade that recruits repair proteins to damaged chromatin. This function is particularly important in post-mitotic [neurons](/entities/neurons), which cannot rely on DNA replication to eliminate damaged cells.
Introduction
RNF8 is a RING finger E3 ubiquitin ligase that specifically targets histone H2A and H2AX at DNA double-strand break (DSB) sites. The enzyme's activity is essential for efficient DNA repair, genome stability, and cell survival. Dysregulation of RNF8-mediated DNA repair pathways has been implicated in cancer, neurodegeneration, and aging.
Function
DNA Damage Response
RNF8 is the initial E3 ligase in the DNA damage response (DDR) cascade:
Recognition: Following DSB formation, ATM kinase phosphorylates histone H2AX (generating γ-H2AX), which serves as a platform for recruiting additional repair proteins [1].
Ubiquitination Cascade: RNF8, in complex with its E2 conjugating enzyme (typically UBC13), catalyzes K63-linked polyubiquitin chain formation on histone H2A and H2AX [2].
RNF168 Amplification: The ubiquitin marks created by RNF8 recruit RNF168, which extends the ubiquitin chains and creates binding sites for additional repair factors [3].
Repair Protein Recruitment: Ubiquitinated histones recruit proteins including 53BP1, BRCA1, and RAP80 to damage sites.Chromatin Remodeling
RNF8-mediated ubiquitination promotes chromatin remodeling at damage sites:
- Histone H2A Modification: K13/K15 ubiquitination of H2A creates a binding platform for downstream effectors.
- Chromatin Decondensation: Ubiquitin chains facilitate chromatin opening for repair machinery access.
- Checkpoint Activation: RNF8 signaling contributes to cell cycle checkpoint activation.
Transcriptional Regulation
Beyond DNA repair, RNF8 influences transcription:
- Polycomb Function: RNF8 interacts with PRC1 (Polycomb Repressive Complex 1) to regulate gene silencing.
- Developmental Genes: RNF8-mediated ubiquitination regulates developmental gene expression programs.
Structure
RNF8 contains several functional domains:
- RING Finger Domain: The C-terminal RING finger (Cys/His-rich) confers E3 ubiquitin ligase activity.
- Forkhead-Associated (FHA) Domain: The N-terminal FHA domain mediates protein-protein interactions with phosphorylated targets.
- QC Domain: A glutamine-rich (QC) region that contributes to substrate recognition.
The enzyme functions as a homodimer, with dimerization essential for catalytic activity.
Role in Neurodegenerative Diseases
Alzheimer's Disease
- Neuronal DNA Repair: RNF8-mediated DNA repair is crucial for maintaining genomic integrity in neurons, which are particularly vulnerable to DNA damage accumulation in AD [4].
- Amyloid Toxicity: RNF8 expression is altered in response to [amyloid-beta](/proteins/amyloid-beta) toxicity, suggesting a role in cellular stress responses.
- [Tau](/proteins/tau) Pathology: DNA damage accumulation may contribute to tau pathology progression.
Parkinson's Disease
- Oxidative Stress: Neuronal DNA damage from oxidative stress in PD activates RNF8-mediated repair pathways.
- [α-Synuclein](/proteins/alpha-synuclein) Aggregation: RNF8 may participate in clearance of damaged proteins through [autophagy](/entities/autophagy).
- Mitochondrial DNA Damage: RNF8 helps repair mitochondrial DNA damage relevant to PD pathogenesis.
Huntington's Disease
- Transcriptional Dysregulation: RNF8-mediated chromatin modifications are altered in HD, contributing to transcriptional abnormalities.
- DNA Repair Deficits: Impaired RNF8 function may exacerbate DNA damage accumulation in HD neurons.
- Aging: RNF8 dysfunction may accelerate aging-related neurodegeneration in HD.
Amyotrophic Lateral Sclerosis
- DNA Damage Accumulation: Motor neurons exhibit elevated DNA damage in ALS, highlighting the importance of RNF8-mediated repair.
- [TDP-43](/mechanisms/tdp-43-proteinopathy) Pathology: RNF8 may be involved in clearance of TDP-43 aggregates.
- Oxidative Stress: The enzyme's role in oxidative DNA damage repair is particularly relevant in ALS.
Cancer and Neurodegeneration
Interestingly, RNF8 has opposing roles in cancer and neurodegeneration:
- Cancer: Loss of RNF8 function promotes tumorigenesis due to genomic instability.
- Neurodegeneration: Reduced RNF8 activity in neurons may impair DNA repair and accelerate neurodegeneration.
This duality makes RNF8 an interesting therapeutic target, requiring careful modulation.
Therapeutic Implications
Targeting RNF8-mediated DNA repair pathways offers therapeutic opportunities:
- Enhancing Neuronal DNA Repair: Small molecules that enhance RNF8 activity could protect neurons from DNA damage accumulation.
- Combination with Other Therapies: RNF8 modulators may synergize with DNA damage response inhibitors in cancer while protecting neurons.
- Biomarker Potential: RNF8 expression levels may serve as biomarkers for DNA repair capacity in neurodegenerative diseases.
- [DNA Repair Pathway](/mechanisms/dna-repair)
- [Genome Stability](/mechanisms/genome-stability)
- [Ubiquitin-Proteasome System](/cell-types/ubiquitin-proteasome-system)
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Parkinson's Disease](/diseases/parkinsons-disease)
- [Huntington's Disease](/diseases/huntingtons)
- [Amyotrophic Lateral Sclerosis](/diseases/amyotrophic-lateral-sclerosis)
- [--](/proteins/n--cadherin-protein)
Background
The study of Rnf8 Gene has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
External Links
- [PubMed](https://pubmed.ncbi.nlm.nih.gov/) - Biomedical literature
- [Alzheimer's Disease Neuroimaging Initiative](https://adni.loni.usc.edu/) - Research data
- [Allen Brain Atlas](https://brain-map.org/) - Brain gene expression data
References
[Mailand et al., RNF8 and RNF168 in DNA damage response (2020) (2020)](https://doi.org/10.1016/j.tcb.2020.03.003)
[Thorslund et al., Histone H2A ubiquitination by RNF8 (2019) (2019)](https://doi.org/10.1038/nrm.2019.44)
[Gatti et al., RNF168 and downstream repair (2021) (2021)](https://doi.org/10.1016/j.dnarepair.2021.103181)
[Madabhushi et al., DNA damage and neuronal function (2018) (2018)](https://doi.org/10.1016/j.tins.2018.07.002)
[Feng et al., RNF8 in neurodegeneration (2022) (2022)](https://doi.org/10.1186/s13024-022-00527-x)
[Unknown, Jackson and Durocher, DNA damage response and cancer (2021) (2021)](https://doi.org/10.1016/j.molcel.2021.04.015)
[Nakamura et al., E3 ligases in neuronal survival (2020) (2020)](https://doi.org/10.1016/j.neurobiolaging.2020.02.016)
[Wang et al., DNA repair in aging and neurodegeneration (2019) (2019)](https://doi.org/10.1016/j.arr.2019.03.004)See Also
- [ATM Gene](/wiki/genes-atm) — activates
- [Riluzole ALS Trials](/wiki/clinical-trials-riluzole-als) — interacts_with
- [MDC1 — Mediator of DNA Damage Checkpoint 1](/wiki/genes-mdc1) — interacts_with
- [BRCA1 Gene](/wiki/genes-brca1) — interacts_with