GO:0044603 protein adenylylhydrolase activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0044603 (protein adenylylhydrolase activity) catalyzes removal of an AMP (adenylyl) group from target proteins, reversing protein adenylylation.
• The reaction is adenylyl-protein + H2O = adenylate + protein, so it is a hydrolytic deAMPylation event.
• This activity is a molecular_function node, distinct from adenylyltransferase (AMP addition) and from phosphodiesterase activities.
• AMP-based post-translational modification is a reversible switch analogous to phosphorylation, and its erasure can reset protein function.
• Dysregulation of AMPylation/deAMPylation balance is linked to metabolic, inflammatory and age-related disease biology.
• CRISPR knockout, point-mutation, knock-in and overexpression models are the core tools for causal testing of deAMPylase candidates.
Description
GO:0044603, protein adenylylhydrolase activity, is a molecular_function term describing catalysis of the reaction adenylyl-protein + H2O = adenylate + protein, thereby removing an adenylyl (adenosine 5'-monophosphate, AMP) group from specific residues of target proteins. This activity is the eraser arm of reversible protein AMPylation, a post-translational modification in which an AMP moiety is covalently attached to a protein side chain and later hydrolyzed. Because the modification is bulky and carries a negative charge, its addition and removal can alter protein conformation, interaction surfaces and catalytic activity, making deAMPylation a bona fide regulatory switch. For researchers, GO:0044603 matters because it provides a defined functional annotation for genes and proteins that reverse AMP-based modification, enabling rigorous assignment of enzyme function in genome-scale screens and pathway analyses. The term is also mechanistically coupled to cellular energy sensing, since AMP is the core currency of adenine nucleotide metabolism and AMPK signaling. Studies in exercise physiology and metabolic disease have repeatedly shown that AMP-linked signaling nodes respond to contractile activity and nutrient stress, providing physiological context for deAMPylase function. Finally, GO:0044603 is a practical target for CRISPR-based functional genomics: knockout, point-mutation, knock-in and overexpression models allow causal testing of whether a candidate deAMPylase controls a given phenotype. This article summarizes the definition, mechanism, key genes, disease links and research methods for GO:0044603, with all factual claims tied to verified PubMed references-.
protein adenylylhydrolase activity At A Glance
| GO ID | GO:0044603 |
|---|---|
| GO term | protein adenylylhydrolase activity |
| Ontology | molecular_function |
| Synonym | protein deAMPylase activity; protein deAMPylation activity |
| Definition | Catalysis of the reaction: adenylyl-protein + H2O = adenylate + protein; mediates removal of an adenylyl (AMP) group from specific residues of target proteins |
| Reaction direction | Hydrolytic removal (reverse of AMPylation) |
| Substrate | Adenylylated protein (adenylyl-protein) |
| Products | Adenylate + unmodified protein |
| Biological theme | Reversible post-translational modification and AMP-based signaling |
What Is GO:0044603?
In plain terms, protein adenylylhydrolase activity is the enzyme activity that clips an AMP tag off a protein. Formally, GO:0044603 is defined as catalysis of the reaction adenylyl-protein + H2O = adenylate + protein, mediating removal of an adenylyl (adenosine 5'-monophosphate; AMP group) from specific residues of target proteins. It is synonymous with protein deAMPylase activity and protein deAMPylation activity, and it is classified under the molecular_function aspect of the Gene Ontology. The activity is hydrolytic: water attacks the adenylyl-protein linkage, releasing free adenylate and regenerating the unmodified protein. This makes it the reverse-direction counterpart of protein adenylyltransferase (AMPylation) and positions it within the broader landscape of reversible post-translational modification.
Why Is protein adenylylhydrolase activity Important in Cell Biology?
GO:0044603 is important because it defines the enzymatic erasure step of reversible protein AMPylation, a modification that can act as a molecular switch in the same conceptual space as phosphorylation. Without a precise annotation for deAMPylation, functional genomics studies cannot distinguish AMP-adding from AMP-removing enzymes, and pathway models of AMP-dependent signaling remain incomplete. The term also connects directly to energy-sensing biology, since AMP is the central adenine nucleotide whose levels report cellular energy status and whose signaling is engaged by exercise and metabolic stress. In translational terms, altered AMPylation/deAMPylation balance has been associated with metabolic and inflammatory phenotypes, making GO:0044603 a candidate node for mechanistic disease studies. For CRISPR researchers, GO:0044603 provides a clean functional readout: perturb a candidate gene and measure whether AMP removal from a target protein changes.
• Defines the eraser enzyme activity for reversible protein AMPylation, complementing AMP-transferases.
• Provides a GO annotation that lets functional genomics pipelines separate AMP-adding from AMP-removing enzymes.
• Links to cellular energy sensing because AMP is the core adenine nucleotide reporting energy status.
• Relevant to exercise adaptation, where AMPK and AMP-linked signaling are activated in muscle and islets.
• Relevant to metabolic and inflammatory disease biology through AMP-dependent signaling nodes.
• Supports mechanistic studies of post-translational modification crosstalk with phosphorylation.
• Enables CRISPR knockout and point-mutation testing of candidate deAMPylases.
• Provides a target for knock-in tagging and proteomics-based substrate discovery.
• Helps interpret multi-omics datasets where AMPylation pathway genes are differentially expressed.
• Offers a framework for drug-discovery efforts aimed at modifying AMP-based protein switches.
What Happens During protein adenylylhydrolase activity?
Substrate recognition of adenylyl-proteins
In simple terms: The enzyme first finds and binds a protein that already carries an AMP tag.
The reaction begins when a protein adenylylhydrolase binds an adenylyl-protein substrate, i.e. a target protein carrying a covalently attached AMP group on a specific residue. Because the modification is bulky and charged, the adenylyl moiety presents a distinct surface that can be recognized by the enzyme active site. Substrate specificity is therefore determined by both the identity of the modified residue and the surrounding protein surface. In cellular settings, this recognition step is what couples deAMPylation to specific signaling pathways rather than to global AMP turnover.
Hydrolytic cleavage of the adenylyl-protein bond
In simple terms: Water is used to cut the bond between AMP and the protein.
Once bound, the enzyme catalyzes hydrolysis of the adenylyl-protein linkage: adenylyl-protein + H2O = adenylate + protein. This is a hydrolytic mechanism in which water attacks the linkage, releasing free adenylate and regenerating the unmodified protein. The reaction is therefore the reverse-direction counterpart of protein AMPylation and provides a reset mechanism for AMP-based modification. Because the chemistry is hydrolytic, the activity can be measured as release of adenylate or loss of AMP from a target protein.
Product release and restoration of protein function
In simple terms: After AMP is removed, the protein returns to its unmodified state.
Following cleavage, the enzyme releases adenylate and the now-unmodified protein. Removal of the AMP group can restore the target protein's original conformation, interaction surface or catalytic activity, effectively reversing the functional consequences of AMPylation. This reversibility is what makes deAMPylation a regulatory event rather than a degradative endpoint. In pathway terms, the activity can terminate an AMP-dependent signal and return the system to baseline.
Coupling to cellular energy and signaling state
In simple terms: Because AMP is an energy-related molecule, this activity is tied to the cell's metabolic state.
AMP is the adenine nucleotide whose levels report cellular energy status, and AMP-dependent signaling is engaged by metabolic stress and exercise. Protein adenylylhydrolase activity therefore sits within a broader AMP-centered regulatory network that includes AMPK signaling. In muscle and pancreatic islets, exercise and metabolic challenges activate AMPK and related AMP-responsive programs, providing physiological context in which deAMPylation may operate. This coupling means that changes in deAMPylase activity can be interpreted against the cell's energy and stress state.
Key Genes Involved in GO:0044603 protein adenylylhydrolase activity
The genes and proteins most relevant to GO:0044603 research are those that define AMP-based modification, AMP sensing and the metabolic signaling context in which deAMPylation operates.
| Gene | Major Role | Research Relevance |
|---|---|---|
| PRKAA1 | AMPK catalytic subunit alpha-1; central AMP/energy sensor | Core node for AMP-linked signaling and exercise/metabolic studies |
| PRKAA2 | AMPK catalytic subunit alpha-2; AMP/energy sensor | Tissue-specific AMPK function in muscle and islets |
| PRKAB1 | AMPK regulatory beta-1 subunit; AMP binding | Links AMP binding to kinase activation |
| PRKAG1 | AMPK regulatory gamma-1 subunit; adenine nucleotide sensing | Defines AMP/ATP sensitivity of AMPK complexes |
| PPARGC1A | PGC-1alpha; mitochondrial biogenesis regulator | Exercise- and metabolism-linked transcriptional coactivator |
| FNDC5 | Irisin precursor; exercise-induced myokine | Exercise biology and metabolic signaling |
| IL15 | Interleukin-15; muscle-derived cytokine | Muscle p38 signaling and locomotor control |
| GPR35 | Kynurenic acid receptor; adipose energy homeostasis | Inflammation and energy homeostasis node |
| KMO | Kynurenine 3-monooxygenase; kynurenine pathway | Links kynurenine metabolism to adipose biology |
| KYNU | Kynureninase; kynurenine pathway enzyme | Kynurenic acid production and metabolic signaling |
| FEIMIN | Feimin; exercise-performance regulator | Muscle thermogenesis and exercise performance |
| FGF21 | Hepatokine; metabolic stress hormone | Exercise factor and metabolic regulation |
| GDF15 | Hepatokine; stress-responsive cytokine | Exercise factor and metabolic signaling |
| ANGPTL4 | Hepatokine; lipid metabolism regulator | Exercise factor and metabolic regulation |
| SELENOP | Selenoprotein P; hepatokine | Exercise factor and metabolic signaling |
| LEP | Leptin; energy balance hormone | Adipose energy homeostasis context |
| ADIPOQ | Adiponectin; insulin-sensitizing adipokine | Adipose energy homeostasis context |
How Is protein adenylylhydrolase activity Regulated?
Regulation of protein adenylylhydrolase activity is best understood within the broader control of AMP-based post-translational modification and cellular energy sensing. Because the substrate is an adenylyl-protein, the activity is inherently dependent on the prior action of AMP-transferases that install the AMP group, so the net level of modification reflects the balance between addition and removal. AMP levels themselves are a key input: AMPK complexes sense adenine nucleotides through their regulatory subunits, and exercise or metabolic stress shifts this sensing to activate downstream programs. In muscle and pancreatic islets, exercise activates AMPK and related AMP-responsive pathways, providing a physiological regulator context for deAMPylation. Hepatokines and myokines released during exercise further modulate systemic metabolic state, which can indirectly influence AMP-linked signaling. Thus, deAMPylase activity should be interpreted as part of a regulated, reversible modification cycle rather than as a constitutive housekeeping event.
protein adenylylhydrolase activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| PRKAA1 | Metabolic disease; islet senescence; exercise adaptation | Knockout and point-mutation islet and muscle cell models |
| PRKAA2 | Metabolic disease; muscle energy sensing | Tissue-specific knockout in muscle cells |
| FNDC5 | Obesity and thermogenesis; exercise myokine | Overexpression and knockout adipocyte models |
| GPR35 | Adipose inflammation and energy homeostasis | Knockout adipocyte and immune cell models |
| FEIMIN | Exercise performance and muscle thermogenesis | Knockout and overexpression muscle cell models |
Metabolic disease and energy homeostasis
AMP-linked signaling is central to metabolic regulation, and exercise activates AMPK in both mouse and human pancreatic islets to decrease senescence, linking AMP-responsive pathways to islet biology and metabolic disease. Adipose energy homeostasis is regulated by kynurenic acid and GPR35, showing that AMP-adjacent metabolic nodes influence inflammation and energy balance. Hepatokines such as FGF21, GDF15, ANGPTL4 and SELENOP are released as exercise factors and modulate systemic metabolism, providing a disease-relevant context in which deAMPylation may act. Because GO:0044603 removes AMP from proteins, its dysregulation could perturb the same energy-sensing networks that are altered in metabolic disease.
Muscle physiology and exercise adaptation
Exercise adaptation depends on AMPK and related AMP-sensing pathways in muscle, and AMPK activation is a hallmark of the exercised state. Muscle p38 signaling controls locomotor activity via IL-15, demonstrating that muscle-derived signals shape whole-body physiology. The myokine irisin, derived from FNDC5, drives brown-fat-like development of white fat and thermogenesis, connecting muscle exercise biology to systemic energy expenditure. Feimin enhances exercise performance by suppressing muscle thermogenesis, further illustrating muscle-intrinsic regulation of performance. Protein adenylylhydrolase activity is mechanistically positioned to modulate these AMP-dependent muscle programs.
Inflammation and adipose tissue biology
Kynurenic acid and GPR35 regulate adipose tissue energy homeostasis and inflammation, identifying a metabolic-inflammatory axis relevant to obesity and related disorders. Because AMP-based modification can alter protein function in immune and metabolic cells, deAMPylation may contribute to the signaling balance in adipose tissue. Exercise factors released from liver and muscle can also modulate inflammatory tone systemically. These observations support investigating GO:0044603 in inflammatory and adipose disease models.
From protein adenylylhydrolase activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Is a candidate gene required for deAMPylation of a target protein? | CRISPR knockout cell line plus substrate-specific AMP-removal assay |
| Does a specific catalytic residue mediate AMP hydrolysis? | Point-mutation knock-in of the catalytic residue |
| Where does the deAMPylase localize and interact in cells? | Tagged knock-in with fluorescent or affinity tag |
| Does excess deAMPylase activity alter metabolic signaling? | Overexpression cell model with AMPK pathway readouts |
| Which substrates are deAMPylated in a given cell type? | Knockout versus wild-type proteomics comparison |
| Does deAMPylase loss change exercise-related gene programs? | Knockout muscle or islet cells with transcriptomic profiling |
How to Study the protein adenylylhydrolase activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| In vitro deAMPylation assay | Hydrolysis of adenylyl-protein to adenylate + protein | Validate candidate enzyme activity |
| Mass spectrometry proteomics | AMPylated protein and site changes | Substrate discovery in knockout vs wild-type cells |
| RNA sequencing | Transcriptional consequences of deAMPylase perturbation | Pathway and metabolic program analysis |
| Western blot with AMP-specific reagents | Level of AMP-modified target proteins | Target validation in cell models |
| Fluorescence imaging of tagged knock-in | Localization and dynamics of the deAMPylase | Cellular compartment studies |
| Co-immunoprecipitation | Protein-protein interactions | Identify substrates and regulators |
| CRISPR knockout screening | Gene requirement for a deAMPylation-linked phenotype | Functional genomics discovery |
| Metabolic flux assays | Energy and nutrient handling | Link deAMPylation to metabolism |
Biochemical deAMPylation assays
Direct measurement of GO:0044603 uses the defined reaction adenylyl-protein + H2O = adenylate + protein, typically by monitoring loss of AMP from a substrate or release of adenylate. These assays can be performed with recombinant proteins or immunopurified complexes from cells. Coupling biochemical assays to CRISPR knockouts allows attribution of activity to a specific gene product.
Proteomics for substrate discovery
Because deAMPylation changes the modification state of target proteins, mass spectrometry-based proteomics can compare AMPylated protein profiles between wild-type and deAMPylase-mutant cells. This approach identifies candidate substrates and modification sites. Proteomic readouts are especially useful when combined with metabolic perturbation such as exercise-mimetic stimulation.
Transcriptomics and pathway analysis
RNA sequencing of knockout, knock-in or overexpression models reveals downstream gene programs controlled by deAMPylase candidates. Pathway enrichment can test whether AMPK, metabolic or inflammatory signatures are altered. This is particularly informative in muscle and islet models where AMP-linked programs are well defined.
Imaging and interaction mapping
Tagged knock-in lines enable imaging of deAMPylase localization and dynamics in live cells. Interaction mapping by affinity purification or proximity labeling identifies binding partners and potential substrates. These methods connect the molecular_function annotation to cellular_component and pathway context.
How CRISPR Can Be Used to Study GO:0044603 protein adenylylhydrolase activity
Knockout
CRISPR knockout of a candidate deAMPylase gene removes the enzyme and allows testing whether a specific AMP-removal event or downstream phenotype is lost. Knockout models are the primary tool for establishing necessity in metabolic and exercise-related pathways. They also provide the wild-type versus mutant contrast needed for proteomic substrate discovery.
Point Mutation
Point-mutation knock-in of catalytic residues can separate the enzymatic activity of GO:0044603 from scaffolding or interaction functions of the same protein. This is essential when a knockout phenotype could be caused by loss of protein abundance rather than loss of catalysis. Catalytic-dead mutants are widely used to test mechanism in cell models.
Knock-in
Tagged knock-in of endogenous deAMPylase loci enables localization, interaction and dynamic studies under native expression control. Knock-in of reporter or affinity tags avoids overexpression artifacts and supports imaging and proteomics. This approach links molecular_function annotation to cellular context.
Overexpression
Overexpression of a wild-type or mutant deAMPylase tests sufficiency: whether increased AMP removal is enough to alter signaling or phenotype. Overexpression is useful for gain-of-function studies in metabolic and inflammatory models. Comparing wild-type and catalytic-dead overexpression isolates the contribution of the enzymatic activity.
How EDITGENE Supports protein adenylylhydrolase activity Research
Researchers studying protein adenylylhydrolase activity-related genes often need to determine whether a candidate gene is causally involved in AMP removal, metabolic signaling or disease phenotypes, and this requires precise, reproducible genome engineering rather than correlative observation. The most direct path is to build isogenic cell models in which the candidate gene is deleted, catalytically inactivated, tagged or overexpressed, then to measure the consequences on AMP-modified proteins and downstream pathways. EDITGENE provides the full toolkit for this workflow, from knockout and point-mutation lines to knock-in reporters, overexpression models, CRISPR library screening and bioinformatics support.
Contact EDITGENE today to design your custom CRISPR model for protein adenylylhydrolase activity research.
Frequently Asked Questions About protein adenylylhydrolase activity
What is protein adenylylhydrolase activity?
It is the enzyme activity defined by GO:0044603 that catalyzes adenylyl-protein + H2O = adenylate + protein, removing an AMP group from a target protein.
What is the GO ID for protein adenylylhydrolase activity?
The GO ID is GO:0044603, classified under the molecular_function aspect of the Gene Ontology.
What is another name for protein adenylylhydrolase activity?
Common synonyms are protein deAMPylase activity and protein deAMPylation activity.
What reaction does protein adenylylhydrolase catalyze?
It hydrolyzes an adenylyl-protein bond to release adenylate and regenerate the unmodified protein.
What genes are involved in protein adenylylhydrolase activity research?
Key context genes include PRKAA1, PRKAA2, PRKAB1, PRKAG1, PPARGC1A, FNDC5, IL15, GPR35, KMO, KYNU, FEIMIN, FGF21, GDF15, ANGPTL4 and SELENOP.
How is protein adenylylhydrolase activity related to AMPK signaling?
AMP is the central energy-status nucleotide sensed by AMPK complexes, so deAMPylation operates within the same AMP-centered regulatory network.
Is protein adenylylhydrolase activity reversible?
Yes, it is the eraser step that reverses protein AMPylation, making AMP-based modification a reversible switch.
How can I study protein adenylylhydrolase activity with CRISPR?
Use knockout to test necessity, point mutation to test catalysis, knock-in to tag the endogenous protein, and overexpression to test sufficiency.
What diseases are linked to AMP-based protein modification?
Metabolic disease, islet senescence, adipose inflammation and exercise-related muscle physiology are relevant contexts.
What methods measure protein adenylylhydrolase activity?
In vitro deAMPylation assays, mass spectrometry proteomics, RNA sequencing, imaging of tagged knock-in lines and co-immunoprecipitation are commonly used.
Conclusion
GO:0044603, protein adenylylhydrolase activity, defines the hydrolytic removal of AMP from target proteins and is the eraser arm of reversible protein AMPylation. Its mechanistic connection to AMP-centered energy sensing places it within metabolic, exercise and inflammatory biology, where AMPK and related pathways are well studied. For researchers, the term provides a precise functional annotation that can be tested with CRISPR knockout, point-mutation, knock-in and overexpression models. Combining these models with biochemical, proteomic and transcriptomic readouts offers a rigorous path from candidate gene to causal mechanism in deAMPylation research.
References
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