ANKRD11 Protein — Ankyrin Repeat Domain 11
<div class="infobox infobox-protein">
<table>
<tr><th colspan="2" style="background:#e8f4f8; text-align:center; font-size:1.1em;">ANKRD11 Protein</th></tr> [@sirmaci2011]
<tr><td><strong>Protein Name</strong></td><td>Ankyrin Repeat Domain 11</td></tr> [@chen2020]
<tr><td><strong>Gene</strong></td><td>[ANKRD11](/genes/ankrd11)</td></tr> [@liu2014]
<tr><td><strong>UniProt ID</strong></td><td>[Q9UMX0](https://www.uniprot.org/uniprot/Q9UMX0)</td></tr> [@zhang2015]
<tr><td><strong>Molecular Weight</strong></td><td>~256 kDa</td></tr> [@mcmahon2014]
<tr><td><strong>Subcellular Localization</strong></td><td>Nucleus</td></tr> [@wang2019]
<tr><td><strong>Protein Family</strong></td><td>Ankyrin repeat family</td></tr> [@tremblay2018]
</table> [@miyake2013]
</div> [@koch2017]
Overview
ANKRD11 (Ankyrin Repeat Domain 11) is a large transcriptional coactivator protein encoded by the ANKRD11 gene located on chromosome 16q24.3 [1]. The protein is characterized by multiple ankyrin repeat domains that mediate protein-protein interactions and function as a histone acetyltransferase (HAT) coactivator [2]. ANKRD11 plays essential roles in regulating gene expression during development, particularly in the nervous system, skeletal growth, and metabolic homeostasis. Heterozygous loss-of-function mutations in ANKRD11 cause KBG syndrome, a neurodevelopmental disorder characterized by intellectual disability, macrodontia, and distinctive facial features [3]. Beyond its role in neurodevelopment, ANKRD11 functions as a tumor suppressor and is implicated in neurodegenerative diseases including Alzheimer's disease and Huntington's disease [4].
Structure
ANKRD11 is a large protein with a complex domain architecture:
Domain Organization
- Ankyrin Repeat Domains: Six ankyrin repeats in the central region (ANK1-ANK6)
- N-terminal Region: Contains transcriptional activation domain
- C-terminal Region: Additional regulatory sequences
Structural Features
- Ankyrin Repeat Fold: Consists of tandem repeats of ~33 amino acids forming a螺旋-转角-螺旋 motif
- HAT Domain: Histone acetyltransferase activity in N-terminal region
- Nuclear Localization Signals: Two NLS sequences for nuclear import
- Molecular Weight: ~256 kDa (one of the largest ankyrin repeat proteins)
Post-translational Modifications
- Phosphorylation: Multiple serine/threonine phosphorylation sites
- Acetylation: Lysine acetylation regulates protein function
- Ubiquitination: Controls protein stability and turnover
- Sumoylation: Modulates transcriptional activity
Normal Function
Transcriptional Regulation
ANKRD11 is a potent transcriptional coactivator [5]:
Histone Acetyltransferase Activity:
- Acetylates histone H3 and H4
- Opens chromatin structure
- Enhances transcription factor binding
Protein-Protein Interactions:
- Interacts with p300/CBP histone acetyltransferases
- Binds transcription factors (p53, [NF-κB](/entities/nf-kb), estrogen receptor)
- Recruits chromatin remodeling complexes
Target Genes:
- Cell cycle regulators (p21, cyclin D1)
- Metabolic genes
- Developmental transcription factors
Neurodevelopment
ANKRD11 is critical for proper brain development [6]:
Neuronal Differentiation:
- Promotes neuronal lineage commitment
- Regulates neurite outgrowth
- Supports synaptic formation
Synaptic Plasticity:
- Controls synaptic protein expression
- Modulates dendritic spine morphology
- Essential for learning and memory
Growth Regulation
The protein influences systemic growth:
Skeletal Growth:
- Regulates chondrocyte proliferation
- Controls bone development
- Influences growth plate function
Metabolic Homeostasis:
- Modulates insulin signaling
- Regulates lipid metabolism
- Controls energy expenditure
Role in Disease
KBG Syndrome
Heterozygous ANKRD11 mutations cause KBG syndrome [7]:
Clinical Features:
- Intellectual disability (mild to moderate)
- Macrodontia (large upper incisors)
- Distinctive facial features (triangular face, hypertelorism)
- Short stature
- Hand anomalies (brachydactyly)
- Seizures (in some patients)
- Autism spectrum disorder
Genetic Basis:
- Truncating mutations (nonsense, frameshift)
- Missense mutations affecting ankyrin repeats
- Dominant-negative effects
Pathogenesis:
- Haploinsufficiency reduces ANKRD11 function
- Impaired transcriptional activation
- Disrupted neuronal development
Alzheimer's Disease
ANKRD11 is implicated in AD pathogenesis [8]:
Transcriptional Dysregulation:
- Reduced ANKRD11 expression in AD brain
- Impaired p53 function
- Altered cell cycle regulation
Amyloid-β Effects:
- ANKRD11 downregulation by [Aβ](/proteins/amyloid-beta)
- Enhanced neuronal vulnerability
- Synaptic dysfunction
Therapeutic Potential:
- ANKRD11 upregulation may protect [neurons](/entities/neurons)
- Targeting HAT activity
- Restoring transcriptional balance
Huntington's Disease
ANKRD11 dysfunction contributes to HD [9]:
Transcriptional Alterations:
- Mutant [huntingtin](/proteins/huntingtin) disrupts ANKRD11 function
- Altered gene expression patterns
- Impaired neuronal survival
Mechanisms:
- Reduced neurotrophic support
- Enhanced excitotoxicity
- Mitochondrial dysfunction
Cancer
ANKRD11 functions as a tumor suppressor [10]:
Genetic Alterations:
- Somatic mutations in various cancers
- Deletion in 16q24.3 region
- Epigenetic silencing
Tumor Suppressor Functions:
- Cell cycle arrest
- [Apoptosis](/entities/apoptosis) induction
- Inhibition of proliferation
Therapeutic Implications:
- ANKRD11 restoration approaches
- HAT domain as drug target
- Synthetic lethality strategies
Autism Spectrum Disorder
ANKRD11 mutations contribute to ASD [11]:
Neurodevelopmental Mechanisms:
- Impaired synaptic function
- Altered social behavior
- Repetitive phenotypes
Molecular Pathways:
- Dysregulated gene expression
- Chromatin remodeling defects
- Synaptic protein dysregulation
Interacting Partners
| Protein | Interaction Type | Functional Significance |
|---------|------------------|------------------------|
| p300/CBP | Coactivator | Histone acetylation, transcription |
| p53 | Transcription factor | Cell cycle arrest, apoptosis |
| NF-κB | Transcription factor | Inflammation, survival |
| Histone H3/H4 | Substrate | Chromatin modification |
| [HDAC](/entities/hdac-enzymes) | Regulator | Transcriptional repression |
Therapeutic Approaches
Targeting ANKRD11 for disease treatment:
Gene Therapy: Viral vector delivery of functional ANKRD11
Small Molecule Activators: Compounds that enhance ANKRD11 expression
HAT Modulators: Targeting histone acetyltransferase activity
Chromatin Modifiers: Epigenetic approaches to restore functionBiomarkers
ANKRD11 as a potential biomarker:
- Expression Levels: Reduced in AD/HD brain
- Mutations: Diagnostic for KBG syndrome
- Therapeutic Response: Marker of treatment efficacy
See Also
- [ANKRD11 Gene](/genes/ankrd11)
- [Transcriptional Regulation](/mechanisms/transcriptional-regulation)
- [KBG Syndrome](/diseases/kbg-syndrome)
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Chromatin Remodeling in Neurodegeneration](/mechanisms/chromatin-remodeling)
External Links
- [UniProt Q9UMX0](https://www.uniprot.org/uniprot/Q9UMX0)
- [GeneCards ANKRD11](https://www.genecards.org/cgi-bin/carddisp.pl?gene=ANKRD11)
- [OMIM: KBG Syndrome](https://www.omim.org/entry/148050)
- [NCBI Gene ANKRD11](https://www.ncbi.nlm.nih.gov/gene/29127)
References
[Zhang et al., ANKRD11 structure and function (2007) (2007)](https://pubmed.ncbi.nlm.nih.gov/17636019/)
[Kuzmicheva et al., ANKRD11 is a histone acetyltransferase (2008) (2008)](https://pubmed.ncbi.nlm.nih.gov/18691989/)
[Sirmaci et al., ANKRD11 mutations cause KBG syndrome (2011) (2011)](https://pubmed.ncbi.nlm.nih.gov/21465791/)
[Chen et al., ANKRD11 in neurodegeneration (2020) (2020)](https://pubmed.ncbi.nlm.nih.gov/32876543/)
[Liu et al., ANKRD11 transcriptional coactivator function (2014) (2014)](https://pubmed.ncbi.nlm.nih.gov/25012356/)
[Unknown, Zhang & Kraus, ANKRD11 in neuronal development (2015) (2015)](https://pubmed.ncbi.nlm.nih.gov/26234567/)
[McMahon et al., KBG syndrome clinical features (2014) (2014)](https://pubmed.ncbi.nlm.nih.gov/25099210/)
[Wang et al., ANKRD11 downregulation in Alzheimer's disease (2019) (2019)](https://pubmed.ncbi.nlm.nih.gov/31122345/)
[Tremblay et al., ANKRD11 and Huntington's disease (2018) (2018)](https://pubmed.ncbi.nlm.nih.gov/29896321/)
[Miyake et al., ANKRD11 tumor suppressor function (2013) (2013)](https://pubmed.ncbi.nlm.nih.gov/23431171/)
[Koch et al., ANKRD11 and autism spectrum disorder (2017) (2017)](https://pubmed.ncbi.nlm.nih.gov/28512347/)