GO:0018345 protein palmitoylation: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0018345 protein palmitoylation is the covalent attachment of a palmitoyl group to a protein, typically on cysteine residues via a thioester bond.
• The reaction is reversible and dynamically controlled by DHHC-family palmitoyl acyltransferases (writers) and acyl protein thioesterases such as APT1 and APT2 (erasers).
• Palmitoylation regulates protein membrane affinity, trafficking, stability, and protein-protein interactions, making it a key switch in cell signaling.
• Dysregulated palmitoylation is implicated in cancer, renal fibrosis, ferroptosis suppression, immunity, and neurological disorders.
• Key enzymes and substrates include ZDHHC9, ZDHHC20, APT1 (LYPLA1), APT2 (LYPLA2), and substrate proteins such as β-catenin and GPX4.
• CRISPR knockout, point-mutation knock-in, and overexpression models are essential to dissect causal roles of palmitoylation enzymes and acceptor sites.
Description
Protein palmitoylation (GO:0018345) is a reversible lipid modification in which a 16-carbon palmitoyl group is covalently attached to a protein, most commonly to cysteine thiols, forming a thioester linkage. This process, also called S-palmitoylation, increases protein hydrophobicity and often promotes association with cellular membranes, thereby influencing protein localization, stability, and function. Unlike many other lipid modifications, palmitoylation is dynamic and can be rapidly added or removed, allowing cells to tune signaling events in response to stimuli. Because of its reversibility and widespread occurrence, protein palmitoylation is now recognized as a central regulatory mechanism in physiology and disease. Researchers study GO:0018345 to understand how membrane targeting, protein trafficking, and signaling networks are controlled, and to identify therapeutic opportunities in cancer, fibrosis, immunity, and ferroptosis-related pathologies.
protein palmitoylation At A Glance
| GO ID | GO:0018345 |
|---|---|
| GO term | protein palmitoylation |
| Ontology | biological_process |
| Synonym | protein amino acid palmitoylation |
| Definition | The covalent attachment of a palmitoyl group to a protein. |
| Major function | Reversible lipid modification that regulates protein membrane association, trafficking, stability, and interactions. |
| Key enzymes | DHHC-family palmitoyl acyltransferases (writers); acyl protein thioesterases APT1/APT2 (erasers). |
| Substrate example | β-catenin, GPX4, and many signaling proteins. |
| Disease relevance | Cancer, renal fibrosis, ferroptosis, immunity, and neurological disorders. |
What Is GO:0018345?
According to the Gene Ontology, GO:0018345 protein palmitoylation is defined as the covalent attachment of a palmitoyl group to a protein. In practice, this usually refers to S-palmitoylation, where the palmitate is linked to a cysteine residue via a labile thioester bond, although N-palmitoylation on other residues can occur. The modification is catalyzed by palmitoyl acyltransferases and reversed by thioesterases, making it a reversible and regulated process.
Why Is protein palmitoylation Important in Cell Biology?
Protein palmitoylation is essential for dynamic control of protein localization and signaling, and its dysregulation contributes to major human diseases including cancer, fibrosis, and immune disorders. Because the modification is reversible, it offers a tunable regulatory node that can be targeted therapeutically, and understanding its mechanisms can reveal biomarkers and drug targets.
• Controls membrane targeting and trafficking of signaling proteins such as Ras and β-catenin.
• Regulates protein stability and degradation, influencing oncogenic pathways.
• Modulates immune signaling and host defense through palmitoylation of immune receptors and effectors.
• Suppresses ferroptosis by regulating GPX4 localization and function.
• Drives renal fibrosis via β-catenin palmitoylation and DHHC9/APT1 balance.
• Provides reversible switches that can be targeted by small molecules or genetic tools.
• Enables spatial and temporal control of protein function at membranes.
• Is frequently altered in tumors and affects the tumor immune microenvironment.
• Serves as a model for studying lipid-based post-translational modifications.
• Offers opportunities for CRISPR-based functional genomics of palmitoylation enzymes.
What Happens During protein palmitoylation?
Substrate recognition and enzyme recruitment
In simple terms: The enzyme finds the target protein and gets ready to attach a fatty acid.
Palmitoyl acyltransferases of the DHHC family recognize substrate proteins through sequences or motifs near the modification site, often in the context of membranes. This step determines specificity and is regulated by protein-protein interactions and membrane composition.
Covalent attachment of palmitate
In simple terms: A fatty acid called palmitate is chemically linked to the protein.
The enzyme catalyzes the transfer of palmitate from palmitoyl-CoA to a cysteine residue on the substrate, forming a thioester bond. This covalent attachment increases the protein's hydrophobicity and promotes membrane association.
Membrane anchoring and trafficking
In simple terms: The modified protein now sticks to membranes and moves to the right place.
Palmitoylation enhances the affinity of proteins for lipid bilayers, facilitating their localization to specific membrane domains such as lipid rafts and affecting trafficking between organelles. This is critical for signaling proteins like β-catenin.
Reversal by thioesterases
In simple terms: The fatty acid can be removed to switch the protein's location or activity.
Acyl protein thioesterases such as APT1 and APT2 hydrolyze the thioester bond, releasing palmitate and allowing the protein to cycle between membrane and soluble pools. This reversibility is essential for dynamic regulation of signaling.
Functional consequences
In simple terms: The addition or removal of palmitate changes what the protein does.
Palmitoylation can alter protein stability, interactions, and activity, impacting processes such as cell proliferation, immune responses, and ferroptosis. Dysregulation of this cycle contributes to disease.
Key Genes Involved in GO:0018345 protein palmitoylation
The following genes and proteins are central to protein palmitoylation (GO:0018345), including writers, erasers, and well-characterized substrates.
| Gene | Major Role | Research Relevance |
|---|---|---|
| ZDHHC9 | Palmitoyl acyltransferase (writer) | Modulates β-catenin palmitoylation in renal fibrosis. |
| ZDHHC20 | Palmitoyl acyltransferase (writer) | Implicated in cancer and immune signaling. |
| ZDHHC2 | Palmitoyl acyltransferase (writer) | Regulates neuronal and cancer-related proteins. |
| ZDHHC3 | Palmitoyl acyltransferase (writer) | Affects AMPA receptor trafficking and synaptic plasticity. |
| ZDHHC5 | Palmitoyl acyltransferase (writer) | Regulates cell adhesion and signaling. |
| ZDHHC7 | Palmitoyl acyltransferase (writer) | Modifies sex steroid receptors and signaling proteins. |
| APT1 (LYPLA1) | Acyl protein thioesterase (eraser) | Modulates β-catenin and fibrosis. |
| APT2 (LYPLA2) | Acyl protein thioesterase (eraser) | Regulates protein depalmitoylation in cancer. |
| β-catenin (CTNNB1) | Substrate | Palmitoylation affects stability and fibrosis. |
| GPX4 | Substrate | Palmitoylation suppresses ferroptosis. |
| Ras (HRAS, KRAS, NRAS) | Substrate | Palmitoylation required for membrane targeting and oncogenesis. |
| GAP43 | Substrate | Neuronal growth cone protein regulated by palmitoylation. |
| PSD-95 | Substrate | Postsynaptic scaffold regulated by palmitoylation. |
| CD4 | Substrate | Immune receptor palmitoylation affects signaling. |
| CD8 | Substrate | Palmitoylation modulates T cell responses. |
| IFITM3 | Substrate | Palmitoylation affects antiviral activity. |
| Calnexin | Substrate | Palmitoylation influences ER functions. |
| eNOS (NOS3) | Substrate | Palmitoylation regulates nitric oxide production. |
How Is protein palmitoylation Regulated?
Protein palmitoylation is regulated at multiple levels. The expression and activity of DHHC enzymes and thioesterases are controlled by transcription, post-translational modifications, and protein-protein interactions. Substrate availability and membrane lipid composition also influence the reaction. In cancer, oncogenic signaling pathways can alter the balance of writers and erasers, leading to changes in substrate palmitoylation. For example, DHHC9 and APT1 modulate β-catenin palmitoylation in renal fibrosis, demonstrating that the equilibrium between these enzymes is critical. Additionally, palmitoylation of GPX4 is regulated to suppress ferroptosis, linking this modification to redox homeostasis. Immune signaling also relies on dynamic palmitoylation of receptors and effectors.
protein palmitoylation and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| ZDHHC9 | Renal fibrosis | Knockout or overexpression in kidney fibroblasts |
| APT1 (LYPLA1) | Renal fibrosis | Knockout or inhibitor treatment in renal cells |
| GPX4 | Ferroptosis, cancer | Point mutation at palmitoylation site |
| HRAS | Cancer | Knock-in of palmitoylation-deficient mutant |
| IFITM3 | Antiviral immunity | Palmitoylation-site mutant knock-in |
Cancer
Dysregulated protein palmitoylation contributes to cancer by affecting oncogenic signaling, cell proliferation, and survival. Palmitoylation of Ras proteins is required for their membrane localization and transforming activity, and altered expression of DHHC enzymes and thioesterases has been observed in various tumors. The modification also influences the tumor immune microenvironment, suggesting that targeting palmitoylation could enhance immunotherapy.
Renal fibrosis
Palmitoyltransferase DHHC9 and acyl protein thioesterase APT1 modulate renal fibrosis through regulating β-catenin palmitoylation. This study demonstrates that the balance between palmitoylation and depalmitoylation of β-catenin affects fibrotic gene expression and provides a potential therapeutic target for kidney fibrosis.
Ferroptosis and oxidative stress
Palmitoylation-dependent regulation of GPX4 suppresses ferroptosis, a form of iron-dependent cell death. This modification affects GPX4 membrane localization and function, and its disruption can sensitize cells to ferroptosis, with implications for cancer therapy and neurodegeneration.
Immunity and infection
Protein S-palmitoylation plays critical roles in immunity by regulating immune receptors, signaling molecules, and antiviral effectors. For example, palmitoylation of IFITM3 affects its antiviral activity, and palmitoylation of CD4 and CD8 modulates T cell signaling. Pathogens can also exploit palmitoylation for immune evasion.
From protein palmitoylation-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does ZDHHC9 palmitoylate β-catenin in renal fibrosis? | ZDHHC9 knockout in renal fibroblasts |
| Is GPX4 palmitoylation required for ferroptosis suppression? | GPX4 palmitoylation-site point mutant |
| How does APT1 regulate β-catenin stability? | APT1 overexpression or knockout |
| Does Ras palmitoylation drive tumor growth? | HRAS palmitoylation-deficient knock-in |
| What is the role of IFITM3 palmitoylation in antiviral defense? | IFITM3 palmitoylation mutant knock-in |
| Can targeting DHHC enzymes alter tumor immune microenvironment? | DHHC knockout in syngeneic tumor models |
How to Study the protein palmitoylation Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Click chemistry with alkynyl-palmitate | Global palmitoylation levels | Profiling in cancer cells |
| Acyl-biotin exchange (ABE) | Specific protein palmitoylation | Validation of substrate modification |
| Mass spectrometry | Palmitoylation sites and stoichiometry | Site mapping in proteomes |
| Fluorescence microscopy | Subcellular localization and dynamics | Live-cell imaging of trafficking |
| Co-immunoprecipitation | Protein-protein interactions | Enzyme-substrate binding |
| CRISPR knockout screening | Gene function in palmitoylation | Identifying regulators |
| RNA-seq | Transcriptional changes | Pathway analysis after perturbation |
| Phospho- and palmitoyl-proteomics | Post-translational modification crosstalk | Signaling studies |
Metabolic labeling and click chemistry
Palmitoylation can be detected using alkynyl-palmitate analogs followed by click chemistry and immunoblotting or proteomics, allowing global profiling of palmitoylated proteins.
Acyl-biotin exchange (ABE) and acyl-RAC
These biochemical methods replace palmitate with biotin to enable purification and identification of palmitoylated proteins from cell lysates.
Proteomics and mass spectrometry
Large-scale proteomic approaches identify palmitoylation sites and quantify changes in response to stimuli or disease states, providing systems-level insights.
Imaging and live-cell assays
Fluorescently tagged proteins and reporters can visualize dynamic palmitoylation and membrane trafficking in live cells, revealing spatial and temporal regulation.
How CRISPR Can Be Used to Study GO:0018345 protein palmitoylation
Knockout
CRISPR knockout of DHHC enzymes or thioesterases (e.g., ZDHHC9, APT1) can reveal their roles in substrate palmitoylation and downstream phenotypes such as fibrosis or cancer cell growth.
Point Mutation
Introducing point mutations at palmitoylation sites (e.g., GPX4 cysteine to alanine) via CRISPR knock-in allows precise testing of whether a specific modification is required for protein function.
Knock-in
Knock-in of tagged or mutant alleles (e.g., HRAS palmitoylation-deficient) enables tracking of protein localization and function in vivo.
Overexpression
CRISPR activation or cDNA overexpression of DHHC enzymes can increase palmitoylation of target proteins, helping to establish sufficiency in disease models.
How EDITGENE Supports protein palmitoylation Research
Researchers studying protein palmitoylation-related genes often need to determine whether a candidate gene is causally involved in a specific biological process or disease. EDITGENE provides comprehensive CRISPR-based services to generate knockout, point-mutation, knock-in, and overexpression cell models, as well as CRISPR library screening and bioinformatics support, enabling rigorous functional studies of palmitoylation enzymes and substrates.
Contact EDITGENE today to design your custom CRISPR model for protein palmitoylation research.
Frequently Asked Questions About protein palmitoylation
What is protein palmitoylation (GO:0018345)?
Protein palmitoylation is the covalent attachment of a palmitoyl group to a protein, typically on cysteine residues, and is a reversible lipid modification that regulates protein membrane association and function.
What genes are involved in protein palmitoylation?
Key genes include DHHC-family palmitoyl acyltransferases (e.g., ZDHHC9, ZDHHC20), thioesterases (APT1/LYPLA1, APT2/LYPLA2), and substrate proteins such as β-catenin, GPX4, and Ras.
How does palmitoylation affect protein function?
Palmitoylation increases protein hydrophobicity, promotes membrane localization, and can alter protein stability, interactions, and activity, thereby influencing signaling pathways.
What diseases are linked to protein palmitoylation?
Dysregulated palmitoylation is implicated in cancer, renal fibrosis, ferroptosis-related diseases, immune disorders, and neurological conditions.
What enzymes remove palmitate from proteins?
Acyl protein thioesterases such as APT1 (LYPLA1) and APT2 (LYPLA2) hydrolyze the thioester bond to remove palmitate, reversing the modification.
How can I study protein palmitoylation in the lab?
Common methods include metabolic labeling with alkynyl-palmitate, acyl-biotin exchange, mass spectrometry, and fluorescence imaging, often combined with CRISPR knockout or point mutation models.
What is the role of palmitoylation in cancer?
Palmitoylation regulates oncogenic signaling proteins like Ras and β-catenin, and its dysregulation contributes to tumor growth, survival, and immune evasion.
Can CRISPR be used to study palmitoylation?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models enable precise dissection of palmitoylation enzyme and substrate functions in disease.
What is the difference between palmitoylation and other lipid modifications?
Palmitoylation is reversible and typically targets cysteine residues via a thioester bond, unlike irreversible modifications such as prenylation or myristoylation.
How does palmitoylation regulate ferroptosis?
Palmitoylation of GPX4 is required for its membrane localization and function, and loss of this modification promotes ferroptosis.
Conclusion
Protein palmitoylation (GO:0018345) is a dynamic and reversible lipid modification that controls protein localization, stability, and signaling, with broad implications for cancer, fibrosis, immunity, and ferroptosis. Understanding its mechanisms and key enzymes provides a foundation for therapeutic targeting and biomarker discovery. EDITGENE offers comprehensive CRISPR services to accelerate functional studies of palmitoylation-related genes, from knockout to precise point mutations and library screening.
References
- 1. Ko PJ et al.. 2018. Protein palmitoylation and cancer.. EMBO Rep 19(10) PMID: 30232163
- 2. Zhou B et al.. 2023. Protein palmitoylation in cancer: molecular functions and therapeutic potential.. Mol Oncol 17(1):3-26 PMID: 36018061
- 3. Gu M et al.. 2023. Palmitoyltransferase DHHC9 and acyl protein thioesterase APT1 modulate renal fibrosis through regulating β-catenin palmitoylation.. Nat Commun 14(1):6682 PMID: 37865665
- 4. Huang B et al.. 2025. Palmitoylation-dependent regulation of GPX4 suppresses ferroptosis.. Nat Commun 16(1):867 PMID: 39833225
- 5. Das T et al.. 2021. Protein S-palmitoylation in immunity.. Open Biol 11(3):200411 PMID: 33653086
- 6. Jin J et al.. 2021. Protein palmitoylation and its pathophysiological relevance.. J Cell Physiol 236(5):3220-3233 PMID: 33094504
- 7. S Mesquita F et al.. 2024. Mechanisms and functions of protein S-acylation.. Nat Rev Mol Cell Biol 25(6):488-509 PMID: 38355760
- 8. Chen Y et al.. 2024. Protein S-palmitoylation modification: implications in tumor and tumor immune microenvironment.. Front Immunol 15:1337478 PMID: 38415253
