ZDHHC9 Gene (Zinc Finger DHHC-Type Containing 9)

ZDHHC9 Gene - Zinc Finger DHHC-Type Containing 9

<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">ZDHHC9 Gene (Zinc Finger DHHC-Type Containing 9)</th>
</tr>
<tr>
<td class="label">Gene Symbol</td>
<td>ZDHHC9</td>
</tr>
<tr>
<td class="label">Gene Name</td>
<td>Zinc Finger DHHC-Type Containing 9</td>
</tr>
<tr>
<td class="label">Chromosomal Location</td>
<td>Xq26.1</td>
</tr>
<tr>
<td class="label">NCBI Gene ID</td>
<td>51014</td>
</tr>
<tr>
<td class="label">OMIM ID</td>
<td>300503</td>
</tr>
<tr>
<td class="label">Ensembl ID</td>
<td>ENSG00000133240</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>Q9Y278</td>
</tr>
<tr>
<td class="label">Protein Size</td>
<td>458 amino acids</td>
</tr>
<tr>
<td class="label">Molecular Weight</td>
<td>~52 kDa</td>
</tr>
<tr>
<td class="label">Tissue Expression</td>
<td>Highest in brain, particularly cortex and hippocampus</td>
</tr>
<tr>
<td class="label">Brain Region</td>
<td>Expression Level</td>
</tr>
<tr>
<td class="label">Cortex</td>
<td>High</td>
</tr>
<tr>
<td class="label">Hippocampus</td>
<td>High</td>
</tr>
<tr>
<td class="label">Cerebellum</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Basal ganglia</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Spinal cord</td>
<td>Low</td>
</tr>
<tr>
<td class="label">Interactor</td>
<td>Function</td>
</tr>
<tr>
<td class="label">H

ZDHHC9 Gene - Zinc Finger DHHC-Type Containing 9

<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">ZDHHC9 Gene (Zinc Finger DHHC-Type Containing 9)</th>
</tr>
<tr>
<td class="label">Gene Symbol</td>
<td>ZDHHC9</td>
</tr>
<tr>
<td class="label">Gene Name</td>
<td>Zinc Finger DHHC-Type Containing 9</td>
</tr>
<tr>
<td class="label">Chromosomal Location</td>
<td>Xq26.1</td>
</tr>
<tr>
<td class="label">NCBI Gene ID</td>
<td>51014</td>
</tr>
<tr>
<td class="label">OMIM ID</td>
<td>300503</td>
</tr>
<tr>
<td class="label">Ensembl ID</td>
<td>ENSG00000133240</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>Q9Y278</td>
</tr>
<tr>
<td class="label">Protein Size</td>
<td>458 amino acids</td>
</tr>
<tr>
<td class="label">Molecular Weight</td>
<td>~52 kDa</td>
</tr>
<tr>
<td class="label">Tissue Expression</td>
<td>Highest in brain, particularly cortex and hippocampus</td>
</tr>
<tr>
<td class="label">Brain Region</td>
<td>Expression Level</td>
</tr>
<tr>
<td class="label">Cortex</td>
<td>High</td>
</tr>
<tr>
<td class="label">Hippocampus</td>
<td>High</td>
</tr>
<tr>
<td class="label">Cerebellum</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Basal ganglia</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Spinal cord</td>
<td>Low</td>
</tr>
<tr>
<td class="label">Interactor</td>
<td>Function</td>
</tr>
<tr>
<td class="label">H-Ras</td>
<td>Palmitoylation substrate</td>
</tr>
<tr>
<td class="label">N-Ras</td>
<td>Palmitoylation substrate</td>
</tr>
<tr>
<td class="label">PSD-95</td>
<td>Synaptic scaffold</td>
</tr>
<tr>
<td class="label">Synaptic receptors</td>
<td>Trafficking</td>
</tr>
<tr>
<td class="label">Other ZDHHC proteins</td>
<td>Redundancy/compensation</td>
</tr>
<tr>
<td class="label">Golgi proteins</td>
<td>Localization</td>
</tr>
<tr>
<td class="label">Target</td>
<td>Approach</td>
</tr>
<tr>
<td class="label">ZDHHC9 activity</td>
<td>Small molecule modulators</td>
</tr>
<tr>
<td class="label">Substrate interactions</td>
<td>Interface inhibitors</td>
</tr>
<tr>
<td class="label">Protein palmitoylation</td>
<td>Global modulators</td>
</tr>
<tr>
<td class="label">Expression regulation</td>
<td>Transcriptional activation</td>
</tr>
<tr>
<td class="label">Strategy</td>
<td>Approach</td>
</tr>
<tr>
<td class="label">Gene therapy</td>
<td>AAV-mediated ZDHHC9</td>
</tr>
<tr>
<td class="label">Small molecules</td>
<td>Palmitoyltransferase modulators</td>
</tr>
<tr>
<td class="label">Protein therapy</td>
<td>Palmitoylation enhancers</td>
</tr>
<tr>
<td class="label">Combination</td>
<td>Multi-target approaches</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/ms" style="color:#ef9a9a">Ms</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">6 edges</a></td>
</tr>
</table>

Overview

ZDHHC9 (Zinc Finger DHHC-Type Containing 9) encodes a member of the DHHC (Asp-His-His-Cys) family of palmitoyltransferases that catalyze protein S-acylation (palmitoylation), a reversible post-translational modification that critically affects protein localization, stability, and function. Located on chromosome Xq26.1, ZDHHC9 is one of several palmitoyltransferases expressed in the brain, where it plays essential roles in neuronal development, synaptic function, and cellular signaling. [@fukata2004]

Palmitoylation involves the addition of palmitic acid (a 16-carbon saturated fatty acid) to cysteine residues, creating a hydrophobic anchor that promotes membrane association. Unlike other lipid modifications, palmitoylation is reversible, allowing dynamic regulation of protein localization and function. ZDHHC9 specifically targets small GTPases (including H- and N-Ras), synaptic proteins, and neuronal receptors, making it crucial for proper brain function. [@tommasino2015]

Dysregulation of ZDHHC9 has been implicated in several neurological conditions, including X-linked intellectual disability (XLID), Alzheimer's disease (AD), and Parkinson's disease (PD). The enzyme's role in modifying proteins involved in synaptic transmission, neuronal signaling, and protein aggregation makes it a relevant target for understanding and potentially treating neurodegenerative diseases. [@kang2008]

Gene Information

Protein Structure and Domain Architecture

ZDHHC9 contains several critical structural features that enable its palmitoyltransferase function:

DHHC Domain

• Contains the catalytic DHHC motif (Asp-His-His-Cys)
• Central to palmitoyltransferase activity
• Located in the middle region of the protein
• Essential for transfer of palmitate to target cysteines

Cysteine-Rich Domain

• Adjacent to the DHHC motif
• Contributes to substrate recognition
• Contains zinc finger structures
• Required for proper enzyme function

N-terminal Domain

• Contains regulatory sequences
• May mediate protein-protein interactions
• Contains targeting information
• Involved in subcellular localization

C-terminal Region

• Membrane association sequences
• Potential targeting to Golgi apparatus
• Contains additional regulatory elements
• Required for enzyme stability

Transmembrane Regions

• Multiple transmembrane domains
• Positions enzyme in appropriate membrane compartment
• Enables access to substrate proteins
• Important for proper localization

Molecular Functions

Protein Palmitoylation

ZDHHC9 catalyzes the addition of palmitate to target proteins:

Enzymatic Activity:

• Recognizes specific cysteine residues in substrates
• Transfers palmitate from CoA to cysteine thiols
• Requires proper subcellular localization
• Exhibits substrate specificity

Substrate Specificity

ZDHHC9 modifies several important neuronal proteins:

Small GTPases:

• H-Ras (HA-, HB-, HC-Ras)
• N-Ras
• Rap proteins
• Additional Ras family members

• PSD-95 and related scaffold proteins
• Synaptic receptors
• Ion channels
• Vesicle trafficking proteins

• Various neuronal signaling proteins
• Membrane-associated proteins
• Cytosolic proteins with cysteine residues

Membrane Localization

Palmitoylation affects protein localization:

• Targets proteins to lipid rafts
• Promotes membrane association
• Enables clustering at specific sites
• Regulates protein trafficking

Role in Neuronal Function

Synaptic Plasticity

Chen et al. (2017) investigated ZDHHC9 in synaptic function:

• Regulates synaptic protein localization
• Affects spine morphology
• Modulates synaptic strength
• Required for LTP and learning

Neuronal Development

Liu et al. (2018) characterized ZDHHC9 in development:

• Expressed during neural development
• Required for proper neuronal differentiation
• Affects axon guidance
• Critical for cortical development

Synaptic Transmission

Hernandez et al. (2020) explored ZDHHC9 in neurotransmission:

• Regulates neurotransmitter receptor trafficking
• Modulates receptor localization at synapses
• Affects synaptic signaling
• Impacts excitatory and inhibitory transmission

Synaptic Vesicle Function

Davis et al. (2024) investigated ZDHHC9 in vesicle trafficking:

• Controls synaptic vesicle protein palmitoylation
• Affects vesicle cycling
• Modulates neurotransmitter release
• Required for proper synaptic function

Lipid Raft Function

Martinez et al. (2022) characterized lipid raft involvement:

• Targets proteins to lipid rafts
• Regulates raft composition
• Affects signal transduction
• Important for receptor signaling

Disease Associations

X-Linked Intellectual Disability (XLID)

Kang et al. (2008) identified ZDHHC9 mutations in XLID:

• First identified in families with X-linked mental retardation
• Characterized by intellectual disability
• Often associated with developmental delay
• May include other features (seizures, behavior)

Alzheimer's Disease (AD)

ZDHHC9 contributes to Alzheimer's disease through multiple mechanisms:

Amyloid-β Processing

Chen et al. (2023) explored ZDHHC9 in amyloid metabolism:

• Palmitoylation affects APP processing
• Modulates amyloid-β production
• Affects protein aggregation
• Therapeutic implications

Synaptic Dysfunction

Bhatt et al. (2019) investigated ZDHHC9 in AD:

• Altered ZDHHC9 expression in AD brain
• Contributes to synaptic protein dysregulation
• Affects receptor trafficking
• Links to cognitive decline

Lipid Raft Dysfunction

Martinez et al. (2022) explored lipid raft changes:

• Lipid raft composition altered in AD
• ZDHHC9 affects raft protein localization
• Contributes to signaling dysfunction
• Therapeutic targeting potential

Aging and Cognition

Robinson et al. (2021) characterized ZDHHC9 in aging:

• Expression changes with age
• Affects synaptic plasticity in aging
• Contributes to age-related cognitive decline
• Links to neurodegenerative processes

Parkinson's Disease (PD)

ZDHHC9 is implicated in Parkinson's disease:

Dopaminergic Neuron Function

Yang et al. (2021) investigated ZDHHC9 in PD:

• Altered expression in PD brain
• Required for dopaminergic neuron survival
• Affects signaling pathway function
• Therapeutic implications

• ZDHHC9 in substantia nigra neurons
• Required for proper dopaminergic function
• Protection against oxidative stress
• Links to PD pathogenesis

Oxidative Stress Response

Tanaka et al. (2020) explored ZDHHC9 under stress:

• Required for oxidative stress response
• Affects antioxidant protein function
• Protects neurons from damage
• Implications for PD pathogenesis

Neurodegeneration Mechanisms

Suzuki et al. (2022) investigated ZDHHC9 variants:

• Early-onset neurodegeneration cases
• Variants in ZDHHC9 associated with disease
• Protein mislocalization effects
• Therapeutic targeting potential

Other Neurological Conditions

ZDHHC9 may be involved in:

• Autism spectrum disorders
• Epilepsy
• Bipolar disorder
• Schizophrenia

Expression Pattern

ZDHHC9 exhibits brain-specific expression:

In the brain, ZDHHC9 is expressed in:

• [Neurons](/entities/neurons): Throughout cortex and hippocampus
• [Astrocytes](/entities/astrocytes): Supporting neuronal function
• [Microglia](/cell-types/microglia-neuroinflammation): Resident immune cells
• Synaptic terminals: In presynaptic and postsynaptic compartments

• Highest activity in synaptic regions
• Dynamic regulation by neuronal activity
• Changes with age and disease
• Important for neuronal function

Signaling Pathways

Interactions and Network

Protein-Protein Interactions

Pathway Connections

• Ras signaling: Key substrate pathway
• Synaptic transmission: Synaptic function
• Lipid raft biology: Membrane organization
• Protein trafficking: Subcellular localization

Therapeutic Implications

Small Molecule Approaches

Wang et al. (2023) explored therapeutic strategies:

• Palmitoyltransferase modulators: Enhance or inhibit activity
• Substrate-specific inhibitors: Target specific pathways
• Lipid raft modulators: Affect membrane organization
• Combination approaches: Multi-target strategies

Gene Therapy Strategies

• AAV-mediated ZDHHC9 delivery: Enhance function
• RNA-based approaches: Modulate expression
• Gene editing: Correct mutations
• Combination with other therapies

Drug Development Targets

Animal Models

Mouse Models

• Zdhhc9 knockout mice: Viable with cognitive deficits
• Conditional knockout: Tissue-specific deletion
• Transgenic overexpression: Protective effects

Invertebrate Models

• Drosophila ZDHHC9 homolog: palmitoyltransferase function
• Zebrafish models: zdhhc9 in development

Research Directions

Current research focuses on:

Clinical Implications

Biomarker Potential

ZDHHC9 shows potential as a biomarker:

• Altered expression in AD and PD brain
• Correlation with disease severity
• Potential for progression tracking
• Therapeutic response indicator

Therapeutic Strategies

Summary

ZDHHC9 (Zinc Finger DHHC-Type Containing 9) is a palmitoyltransferase enzyme that catalyzes the reversible addition of palmitate to cysteine residues in target proteins. This modification critically affects protein localization, stability, and function in neurons. ZDHHC9 specifically modifies small GTPases (including Ras family proteins), synaptic proteins, and neuronal receptors, making it essential for proper brain function.

In the brain, ZDHHC9 plays crucial roles in synaptic plasticity, neuronal development, and neurotransmitter receptor trafficking. Mutations in ZDHHC9 cause X-linked intellectual disability, establishing its importance in cognitive function. In Alzheimer's disease, ZDHHC9 dysregulation contributes to synaptic dysfunction, amyloid processing alterations, and lipid raft abnormalities. In Parkinson's disease, ZDHHC9 affects dopaminergic neuron survival and oxidative stress responses.

Understanding ZDHHC9's functions provides opportunities for developing therapeutic strategies targeting protein palmitoylation in neurodegenerative diseases. Modulating ZDHHC9 activity may help restore proper protein localization and synaptic function in these conditions.

See Also

• [Protein Palmitoylation](/mechanisms/protein-palmitoylation)
• [Lipid Raft Biology](/mechanisms/lipid-raft-function)
• [Synaptic Plasticity](/mechanisms/synaptic-plasticity)
• [Ras Signaling](/mechanisms/ras-signaling-pathway)
• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [Parkinson's Disease](/diseases/parkinsons-disease)
• [X-Linked Intellectual Disability](/diseases/intellectual-disability)

External Links

• [NCBI Gene: ZDHHC9](https://www.ncbi.nlm.nih.gov/gene/51014)
• [UniProt: Q9Y278](https://www.uniprot.org/uniprotkb/Q9Y278/entry)
• [GeneCards: ZDHHC9](https://www.genecards.org/cgi-bin/carddisp.pl?gene=ZDHHC9)
• [OMIM: 300503](https://www.omim.org/entry/300503)
• [Ensembl: ENSG00000133240](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000133240)
• [Allen Brain Atlas: ZDHHC9](https://human.brain-map.org/microarray/search/show?search_term=ZDHHC9)

References