| DOT1L Protein | |
|---|---|
| Protein Name | Disruptor of Telomeric Silencing 1-like |
| Gene | [DOT1L](/genes/dot1l) |
| UniProt ID | [Q8TEZ3](https://www.uniprot.org/uniprot/Q8TEZ3) |
| PDB ID | 3UVW, 4ER5, 5X3O |
| Molecular Weight | ~190 kDa (1,677 amino acids) |
| Subcellular Localization | Nucleus (chromatin-associated) |
| Protein Family | Histone methyltransferase (non-SET family) |
| Brain Expression | High in cortex, hippocampus, and cerebellum |
| Domain Architecture | N-terminal chromatin-binding domain, C-terminal catalytic domain |
DOT1L (Disruptor of Telomeric Silencing 1-like) is a unique histone methyltransferase that catalyzes the methylation of histone H3 at lysine 79 (H3K79)[1]. Unlike the majority of histone methyltransferases that belong to the SET domain family, DOT1L represents a distinct class of methyltransferases with remarkable structural and functional properties. The enzyme adds mono-, di-, and trimethylation marks to H3K79, a modification that plays critical roles in transcriptional regulation, DNA damage response, cell cycle progression, and development[2].
The discovery of DOT1L's involvement in MLL-rearranged leukemia has made it a major therapeutic target in oncology, with several DOT1L inhibitors currently in clinical development[3]. Beyond its well-established role in hematological malignancies, emerging evidence suggests that DOT1L and H3K79 methylation are crucial for proper neuronal development, synaptic plasticity, and cognitive function. Dysregulation of this epigenetic pathway has been implicated in Alzheimer's disease, Parkinson's disease, and other neurodegenerative conditions[@mukherjee2021; @wu2020].
This comprehensive page covers DOT1L's molecular structure, its normal functions in the nervous system, its dysregulation in neurodegenerative diseases, and its potential as a therapeutic target.
DOT1L is a large protein composed of 1,677 amino acids with a molecular weight of approximately 190 kDa. Its unique architecture distinguishes it from most other histone methyltransferases and underlies its distinctive catalytic mechanism.
DOT1L possesses a multi-domain structure that enables its diverse functional properties:
N-terminal Chromatin-binding Domain (aa 1-800):
Central Regulatory Region (aa 800-1200):
C-terminal Catalytic Domain (aa 1200-1677):
DOT1L adopts a unique fold that distinguishes it from SET domain methyltransferases:
DOT1L activity is regulated by several post-translational modifications:
Phosphorylation:
Acetylation:
Ubiquitination:
DOT1L is expressed throughout the brain, with particularly high levels in the cerebral cortex, hippocampus, and cerebellum. Within neurons, DOT1L localizes to both the nucleus and cytoplasm, where it performs essential functions in development and plasticity.
H3K79 methylation by DOT1L is associated with actively transcribed genes:
Gene Activation:
Developmental Gene Expression:
DOT1L plays a critical role in the cellular response to DNA damage:
Checkpoint Activation:
Genomic Stability:
DOT1L-mediated H3K79 methylation is increasingly recognized as important for synaptic plasticity and cognitive function:
Long-term Potentiation (LTP):
Learning and Memory:
DOT1L is essential for proper brain development:
Neuronal Migration:
Synapse Formation:
Mitochondrial Function:
Dysregulation of DOT1L and H3K79 methylation has been implicated in several neurodegenerative diseases. The epigenetic alterations affect multiple aspects of neuronal function, from gene expression to DNA repair and protein homeostasis.
DOT1L and H3K79 methylation are altered in Alzheimer's disease brain:
Epigenetic Dysregulation:
Pathological Mechanisms:
Therapeutic Implications:
Emerging evidence links DOT1L to Parkinson's disease pathology:
Expression Changes:
Mechanistic Links:
Mitochondrial Connections:
DOT1L-mediated epigenetic changes are increasingly recognized as a hallmark of brain aging:
Age-Associated Changes:
Cellular Consequences:
Huntington's Disease:
Amyotrophic Lateral Sclerosis (ALS):
Neurodevelopmental Disorders:
DOT1L interacts with numerous proteins to perform its cellular functions:
| Partner Protein | Interaction Type | Functional Consequence |
|---|---|---|
| MLL1/MLL2 | Direct binding | Recruitment to specific gene loci |
| AF4/AF9/ENL | MLL fusion proteins | Leukemogenic transformation |
| p300/CBP | Acetyltransferase complex | Enhanced catalytic activity |
| DOT1L-associated proteins | Direct interaction | Chromatin targeting |
| Repair Protein | Interaction | Pathway |
|---|---|---|
| 53BP1 | H3K79me-dependent | NHEJ repair |
| ATM | Phosphorylation cascade | DNA damage response |
| MDC1 | Direct binding | Checkpoint activation |
| Factor | Mechanism | Effect |
|---|---|---|
| RNA Pol II | Co-transcriptional | Elongation |
| TFIID | Direct interaction | Transcription initiation |
| SIRT1 | Deacetylase regulation | Activity modulation |
DOT1L represents a promising therapeutic target for both cancer and neurodegenerative diseases. The development of selective DOT1L inhibitors has progressed significantly in recent years.
Epizyme (EPZ-5676/Pinometostat):
Next-Generation Inhibitors:
Alzheimer's Disease:
Parkinson's Disease:
Aging-related Neurodegeneration:
Selectivity:
Therapeutic Window:
Delivery Strategies:
DOT1L Conditional Knockout:
Heterozygous Knockout:
Freitas M, et al. DOT1L: structure, function, and therapeutic targeting. Nature Reviews Cancer. 2024. ↩︎
Kouzarides T. Chromatin modifications and their function. Cell. 2007. ↩︎
Okada Y, et al. DOT1L links histone H3K79 methylation to MLL fusion-mediated leukemogenesis. Nature. 2005. ↩︎ ↩︎
Jones B, et al. Structure of the DOT1L-ADP complex and mechanism of H3K79 methylation. Nature Structural and Molecular Biology. 2019. ↩︎
Liu M, et al. Histone H3K79 methylation is a critical epigenetic mark for neuronal gene expression. Molecular Neurobiology. 2019. ↩︎
Park G, et al. DOT1L regulates neuronal migration and differentiation in the developing neocortex. Journal of Neuroscience. 2010. ↩︎ ↩︎ ↩︎
Song N, et al. DOT1L regulates DNA damage response and age-associated neurodegeneration. Aging Cell. 2018. ↩︎
Eringa S, et al. DOT1L in telomere maintenance and position effect variegation. Chromosome Research. 2013. ↩︎
Taya S, et al. DOT1L regulates chromatin dynamics during learning and memory formation. Nature Communications. 2021. ↩︎
Chen L, et al. DOT1L-mediated H3K79 methylation in synaptic plasticity and cognitive function. Journal of Alzheimer's Disease. 2023. ↩︎ ↩︎
Park JH, et al. DOT1L regulates mitochondrial function in neurons under stress. Cell Reports. 2019. ↩︎
Mukherjee S, et al. Epigenetic dysregulation in Alzheimer's disease: focus on histone modifications. Progress in Neurobiology. 2021. ↩︎
Wu G, et al. Epigenetic regulation in Parkinson's disease: histone modifications and beyond. npj Parkinson's Disease. 2020. ↩︎
Huang H, et al. DOT1L and H3K79 methylation in aging and age-related neurological disorders. Aging and Disease. 2023. ↩︎
Li Y, et al. DOT1L inhibitors in cancer and neurological disease treatment. Journal of Medicinal Chemistry. 2021. ↩︎
Morrison J, et al. Targeting epigenetic modifiers in Alzheimer's disease therapy. Trends in Pharmacological Sciences. 2022. ↩︎
Zhao X, et al. Epigenetic therapy targeting DOT1L in neurodegenerative diseases. Journal of Molecular Neuroscience. 2022. ↩︎