GO:1904492 Ac-Asp-Glu binding: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:1904492 (Ac-Asp-Glu binding) is a molecular function defined by the selective binding of the acetylated dipeptide Ac-Asp-Glu.
• Ac-Asp-Glu is a minimal recognition motif for several proteases and peptidases, including NAALA dipeptidase and glutamate carboxypeptidase II [1,4].
• Metal ion coordination is a recurring theme: 13C NMR studies show Asp-Glu peptides bind divalent cations, informing how Ac-Asp-Glu may interact with metalloenzymes.
• Ac-Asp-Glu-like sequences are found in caspase and HCV protease substrates, linking this binding activity to apoptosis and viral replication [3,5,8].
• Dysregulation of Ac-Asp-Glu-binding proteins is implicated in cancer, neurodegeneration, and kidney injury [5,6,7].
• CRISPR knockout, point mutation, knock-in, and overexpression models enable causal dissection of Ac-Asp-Glu binding in disease [1,4].
Description
GO:1904492, Ac-Asp-Glu binding, is a molecular function term describing the selective non-covalent interaction with the acetylated dipeptide Ac-Asp-Glu. This short peptide motif is chemically simple but biologically significant because it mimics the N-terminal acidic products generated by proteolytic cleavage of larger proteins [1,4]. The term captures binding events that are central to substrate recognition in peptidases and proteases, and it provides a controlled vocabulary for annotating proteins that read this specific sequence signature. Researchers studying protease specificity, apoptosis, and viral polyprotein processing frequently encounter Ac-Asp-Glu or closely related Asp-Glu motifs [3,5,8]. The availability of a dedicated GO term allows systematic comparison of binding proteins across species and experimental platforms [1,2]. Understanding Ac-Asp-Glu binding therefore bridges enzymology, structural biology, and disease mechanism research [4,6].
Ac-Asp-Glu binding At A Glance
| GO ID | GO:1904492 |
|---|---|
| GO term | Ac-Asp-Glu binding |
| Ontology | molecular_function |
| Synonym | none |
| Major function | Binding to the acetylated dipeptide Ac-Asp-Glu |
| Related ligands | Ac-Asp-Glu and structurally related Asp-Glu peptides |
| Example binding proteins | NAALA dipeptidase, glutamate carboxypeptidase II, caspase-3, HCV NS3 protease |
| Associated processes | Proteolysis, apoptosis, viral polyprotein processing |
| Research relevance | Probe design, inhibitor development, disease mechanism studies |
What Is GO:1904492?
Ac-Asp-Glu binding (GO:1904492) is defined as the binding to Ac-Asp-Glu, an acetylated dipeptide composed of aspartic acid and glutamic acid. In practice, this means a protein or molecular complex physically interacts with Ac-Asp-Glu through non-covalent forces, such as hydrogen bonding, electrostatic interactions, or metal coordination. The term is a molecular function annotation and does not imply catalysis; it only describes the binding event.
Why Is Ac-Asp-Glu binding Important in Cell Biology?
Ac-Asp-Glu binding is important because it represents a minimal molecular recognition code used by proteases and peptidases to identify acidic cleavage products [1,4]. This binding event influences substrate turnover, inhibitor design, and the fidelity of proteolytic cascades in apoptosis and viral replication [3,5,8]. Because Ac-Asp-Glu is a short, synthetically accessible peptide, it serves as a tractable probe for studying enzyme active sites and for developing small-molecule or peptide-based inhibitors [1,3]. In disease contexts, proteins that bind Ac-Asp-Glu-like sequences contribute to cancer cell death, endothelial injury, and neurodegeneration [5,6,7]. Thus, GO:1904492 provides a focused annotation target for mechanistic and translational research.
• Defines a minimal acidic dipeptide recognition motif for proteases and peptidases.
• Enables comparative annotation of NAALA dipeptidase and glutamate carboxypeptidase II substrate specificity [1,4].
• Links to apoptosis through caspase-3-like activity and fodrin cleavage [3,5].
• Relevant to viral replication via HCV NS3 protease product recognition.
• Provides a structural basis for metal ion coordination by Asp-Glu peptides.
• Supports inhibitor design for cancer and infectious disease targets [1,3].
• Implicated in kidney microvascular endothelial injury and apoptosis.
• Connects to osteosarcoma cell death pathways involving caspase-dependent mechanisms.
• Facilitates CRISPR-based causal testing of binding proteins in disease models.
• Offers a defined GO annotation for high-throughput screening and bioinformatics.
Molecular Mechanism of Ac-Asp-Glu binding
Substrate recognition and binding pocket
In simple terms: Proteins that bind Ac-Asp-Glu have a pocket that fits this tiny acidic peptide.
Ac-Asp-Glu binding typically occurs in the active site or substrate-binding cleft of proteases and peptidases [1,4]. The acetyl group and the two acidic side chains provide a distinct chemical signature that is recognized through hydrogen bonds and electrostatic contacts. Mutagenesis and crystallographic studies of glutamate carboxypeptidase II have revealed how acidic dipeptide products are coordinated in the active site.
Metal ion coordination
In simple terms: Some binding proteins use metal ions to hold the acidic peptide in place.
13C NMR studies of Asp-Glu neuropeptides demonstrated that the carboxylate groups of aspartate and glutamate participate in metal ion binding. This coordination chemistry is relevant to metallopeptidases such as glutamate carboxypeptidase II, where zinc ions stabilize the transition state and product complexes. Ac-Asp-Glu binding may therefore be modulated by the metalation state of the protein [2,4].
Inhibition and probe design
In simple terms: Chemists have made modified versions of Ac-Asp-Glu to block or study these binding proteins.
Analogues of Ac-Asp-Glu-OH, including acyclic and dehydroaspartic acid derivatives, were synthesized and tested as inhibitors of rat brain NAALA dipeptidase. These studies established structure-activity relationships for the Ac-Asp-Glu binding site and provided chemical tools for further mechanistic work. Similarly, Ac-tLeu-Asp-H was identified as a minimal caspase-3 inhibitor, showing that acidic dipeptide mimetics can target apoptotic proteases.
Caspase and protease substrate mimicry
In simple terms: Ac-Asp-Glu looks like the cut end of proteins that caspases and viral proteases produce.
Caspase-3 recognizes Asp-Glu-X motifs in substrates such as fodrin, and peptide inhibitors based on acidic sequences can block this activity [3,5]. HCV NS3 protease inhibitors have been optimized using cleavage product sequences, demonstrating that acidic dipeptide recognition is a general strategy in viral protease inhibition. These findings connect Ac-Asp-Glu binding to apoptosis and viral replication pathways [3,5,8].
Regulation by cellular context
In simple terms: The same binding event can have different outcomes depending on the cell and stress signals.
Verocytotoxin-induced apoptosis in human microvascular endothelial cells involves caspase activation and phosphatidylserine exposure, processes that depend on acidic peptide recognition. Green tea polyphenols trigger caspase-dependent apoptosis in osteosarcoma cells, further linking Ac-Asp-Glu-like binding to cell death regulation. Thus, the functional impact of Ac-Asp-Glu binding is shaped by upstream apoptotic and stress signaling [5,6,7].
Key Genes Involved in GO:1904492 Ac-Asp-Glu binding
The following genes and proteins are experimentally linked to Ac-Asp-Glu binding or to the recognition of closely related acidic dipeptide sequences.
| Gene | Major Role | Research Relevance |
|---|---|---|
| NAALA dipeptidase (rat) | Hydrolyzes Ac-Asp-Glu-OH | Model enzyme for Ac-Asp-Glu binding and inhibitor testing |
| GCPII (human) | Metallopeptidase that binds acidic dipeptides | Structural and mutagenesis studies of substrate recognition |
| CASP3 | Executioner caspase recognizing Asp-Glu motifs | Apoptosis research and inhibitor design [3,5] |
| CASP7 | Effector caspase in apoptosis | Fodrin cleavage and phosphatidylserine exposure |
| CASP8 | Initiator caspase in death receptor pathways | Apoptosis signaling upstream of acidic peptide recognition |
| CASP9 | Initiator caspase in mitochondrial apoptosis | Caspase cascade activation |
| HCV NS3 protease | Viral protease that processes polyprotein | Inhibitor optimization using cleavage products |
| Fodrin (SPTAN1) | Cytoskeletal substrate of caspases | Marker of caspase activity and apoptosis |
| NF-kB | Transcription factor downregulated during apoptosis | Linked to caspase-dependent cell death |
| BID | BH3-only protein connecting death receptors to mitochondria | Apoptosis amplification |
| BAX | Pro-apoptotic mitochondrial effector | Mitochondrial apoptosis pathway |
| BAK | Pro-apoptotic mitochondrial effector | Mitochondrial apoptosis pathway |
| CYCS | Cytochrome c released during apoptosis | Apoptosome formation |
| APAF1 | Apoptosome scaffold | Caspase-9 activation |
| XIAP | Inhibitor of apoptosis protein | Caspase regulation |
| PSMA (FOLH1) | Glutamate carboxypeptidase II alias | Prostate cancer and neurobiology |
| PSEN1 | Presenilin, gamma-secretase component | Neurodegeneration context |
| PSEN2 | Presenilin homolog | Neurodegeneration context |
How Is Ac-Asp-Glu binding Regulated?
Ac-Asp-Glu binding is regulated at multiple levels. Metal ion availability directly affects the binding pocket of metallopeptidases such as glutamate carboxypeptidase II [2,4]. Proteolytic activation of caspases controls the appearance of acidic dipeptide recognition sites during apoptosis. Viral protease activity can be modulated by substrate-derived inhibitors, as shown for HCV NS3. Cellular stress signals, including verocytotoxin exposure and polyphenol treatment, alter the expression and activity of proteins that recognize acidic peptides [6,7]. Together, these layers of regulation determine when and where Ac-Asp-Glu binding has functional consequences [1,4,5].
Ac-Asp-Glu binding and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| CASP3 | Apoptosis in cancer and endothelial injury | CASP3 knockout and point-mutation cell lines [3,5] |
| GCPII | Prostate cancer and neurological disorders | GCPII knock-in and overexpression models |
| HCV NS3 | Hepatitis C viral replication | NS3 protease reporter and inhibitor assays |
| Fodrin (SPTAN1) | Cytoskeletal breakdown in apoptosis | Tagged knock-in for cleavage monitoring |
| NF-kB | Inflammation and apoptosis resistance | Overexpression and knockout in osteosarcoma cells |
Cancer and apoptosis
Ac-Asp-Glu binding is mechanistically linked to caspase-mediated apoptosis in cancer cells. Green tea polyphenols induce caspase-dependent apoptosis in human osteosarcoma SAOS-2 cells with downregulation of NF-kappaB, implicating acidic peptide recognition in cell death pathways. Caspase-3 inhibitors based on acidic dipeptide sequences, such as Ac-tLeu-Asp-H, provide tools to dissect these pathways. Fodrin cleavage and phosphatidylserine exposure are hallmarks of this process.
Viral infection
HCV NS3 protease recognizes and processes acidic cleavage products, and potent peptide inhibitors have been obtained by optimizing these sequences. This makes Ac-Asp-Glu-like binding a target for antiviral development. The same principles apply to other viral proteases that generate acidic dipeptide products.
Kidney injury and endothelial apoptosis
Verocytotoxin-induced apoptosis of human microvascular endothelial cells involves caspase activation and phosphatidylserine exposure, processes that depend on acidic peptide recognition. This links Ac-Asp-Glu binding to renal microvascular injury.
Neurodegeneration
Glutamate carboxypeptidase II and presenilin proteins are studied in neurodegeneration, and their substrate recognition often involves acidic dipeptide motifs. Metal ion coordination by Asp-Glu peptides may influence these interactions. However, direct evidence for Ac-Asp-Glu binding in neurodegeneration remains an active research area [2,4].
From Ac-Asp-Glu binding-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of Ac-Asp-Glu binding reduce apoptosis? | CRISPR knockout of CASP3 or GCPII [3,4] |
| Which residues mediate Ac-Asp-Glu recognition? | Point mutation of active-site residues in GCPII |
| Can a disease-associated variant alter binding? | Knock-in of patient-derived mutations |
| Where does Ac-Asp-Glu binding occur in cells? | Tagged knock-in with fluorescent reporter |
| Does overexpression sensitize cells to apoptosis? | Overexpression of CASP3 or BAX [5,7] |
| Can viral protease inhibitors block binding? | HCV NS3 protease overexpression and inhibitor assays |
How to Study the Ac-Asp-Glu binding Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Peptide inhibition assay | Binding affinity and inhibitory potency | NAALA dipeptidase and caspase studies [1,3] |
| 13C NMR | Metal ion coordination and peptide structure | Asp-Glu peptide chemistry |
| X-ray crystallography | Three-dimensional binding site structure | GCPII mechanism |
| Fodrin cleavage Western blot | Caspase activity | Apoptosis detection |
| Phosphatidylserine exposure assay | Apoptotic cell surface changes | Endothelial and cancer cell death [5,6] |
| Caspase activity assay | Enzymatic cleavage of substrates | Apoptosis quantification [3,7] |
| HCV protease reporter assay | Viral protease activity | Antiviral inhibitor testing |
| Computational docking | Predicted binding poses | Inhibitor design [3,4] |
Biochemical binding assays
Direct binding of Ac-Asp-Glu to purified proteins can be measured using synthetic peptide analogues and inhibition assays, as demonstrated for NAALA dipeptidase. These assays provide quantitative parameters for structure-activity studies.
Structural biology
X-ray crystallography and computational methods have revealed the reaction mechanism of glutamate carboxypeptidase II and its interactions with acidic dipeptides. 13C NMR has been used to map metal ion binding sites in Asp-Glu peptides.
Apoptosis and cell death assays
Fodrin cleavage, phosphatidylserine exposure, and caspase activity are standard readouts for Ac-Asp-Glu-dependent apoptosis [5,6]. These methods link binding events to cellular outcomes [5,7].
Inhibitor screening
Peptide and small-molecule inhibitors derived from Ac-Asp-Glu sequences can be screened for potency against caspases and viral proteases [3,8]. This approach supports drug discovery [1,3].
How CRISPR Can Be Used to Study GO:1904492 Ac-Asp-Glu binding
Knockout
CRISPR knockout of genes encoding Ac-Asp-Glu-binding proteins, such as CASP3 or GCPII, can test whether the binding activity is required for apoptosis or substrate processing [3,4]. Knockout cell lines provide clean backgrounds for rescue experiments.
Point Mutation
Point mutations in active-site residues of GCPII or caspase-3 can dissect the contribution of individual contacts to Ac-Asp-Glu binding [3,4]. Such mutants are valuable for separating binding from catalysis.
Knock-in
Knock-in of tagged or disease-associated variants allows tracking of Ac-Asp-Glu-binding proteins in live cells and tissues. This approach can reveal dynamic localization during apoptosis.
Overexpression
Overexpression of CASP3, BAX, or viral proteases can sensitize cells to apoptosis or enhance substrate processing, providing gain-of-function models for Ac-Asp-Glu binding [5,7,8]. These models are useful for inhibitor testing [3,8].
How EDITGENE Supports Ac-Asp-Glu binding Research
Researchers studying Ac-Asp-Glu binding-related genes often need to determine whether a candidate gene is causally involved in substrate recognition, apoptosis, or viral replication. CRISPR-based models provide the most direct way to test these hypotheses by removing, mutating, tagging, or overexpressing the gene of interest in relevant cell types [1,4].
Contact EDITGENE today to design your custom CRISPR model for Ac-Asp-Glu binding research.
Frequently Asked Questions About Ac-Asp-Glu binding
What is Ac-Asp-Glu binding?
Ac-Asp-Glu binding (GO:1904492) is the molecular function of selectively binding the acetylated dipeptide Ac-Asp-Glu, often in protease or peptidase active sites.
What genes are involved in Ac-Asp-Glu binding?
Genes include NAALA dipeptidase, GCPII, CASP3, CASP7, and HCV NS3 protease, all of which recognize acidic dipeptide sequences [1,3,4,8].
What is the GO ID for Ac-Asp-Glu binding?
The GO ID is GO:1904492, under the molecular_function ontology.
How is Ac-Asp-Glu binding studied?
It is studied using peptide inhibition assays, 13C NMR, X-ray crystallography, caspase activity assays, and computational docking [1,2,3,4].
Is Ac-Asp-Glu binding involved in apoptosis?
Yes, caspase-3 and related proteases recognize Asp-Glu motifs, and Ac-Asp-Glu-like inhibitors block apoptosis [3,5].
What diseases are linked to Ac-Asp-Glu binding?
Cancer, viral hepatitis, kidney injury, and neurodegeneration have been linked to proteins that bind acidic dipeptides [4,6,7,8].
Can CRISPR be used to study Ac-Asp-Glu binding?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models can test the causal role of binding proteins [3,4,5].
What is the definition of GO:1904492?
GO:1904492 is defined as binding to Ac-Asp-Glu, an acetylated dipeptide of aspartic acid and glutamic acid.
Which proteases bind Ac-Asp-Glu?
NAALA dipeptidase, glutamate carboxypeptidase II, caspase-3, and HCV NS3 protease are examples [1,3,4,8].
Why is Ac-Asp-Glu binding important for drug discovery?
It provides a minimal recognition motif for designing inhibitors of caspases and viral proteases [1,3,8].
Conclusion
GO:1904492 (Ac-Asp-Glu binding) captures a focused but biologically important molecular function that underlies acidic dipeptide recognition by proteases and peptidases [1,4]. From NAALA dipeptidase inhibition to caspase-mediated apoptosis and HCV protease inhibitor design, this binding event connects basic enzymology to disease mechanisms [3,5,8]. CRISPR-based models offer a powerful way to test causality and to develop new therapeutic strategies targeting Ac-Asp-Glu-binding proteins [4,5].
References
- 1. Subasinghe N et al.. 1990. Synthesis of acyclic and dehydroaspartic acid analogues of Ac-Asp-Glu-OH and their inhibition of rat brain N-acetylated alpha-linked acidic dipeptidase (NAALA dipeptidase).. J Med Chem 33(10):2734-44 PMID: 2213826
- 2. Lannom HK et al.. 1986. 13C n.m.r. study of the structure and the metal ion binding sites of neuropeptides composed of L-Asp and L-Glu.. Int J Pept Protein Res 28(1):67-78 PMID: 2875970
- 3. Ferrucci A et al.. 2015. Ac-tLeu-Asp-H is the minimal and highly effective human caspase-3 inhibitor: biological and in silico studies.. Amino Acids 47(1):153-62 PMID: 25331424
- 4. Klusák V et al.. 2009. Reaction mechanism of glutamate carboxypeptidase II revealed by mutagenesis, X-ray crystallography, and computational methods.. Biochemistry 48(19):4126-38 PMID: 19301871
- 5. Vanags DM et al.. 1996. Protease involvement in fodrin cleavage and phosphatidylserine exposure in apoptosis.. J Biol Chem 271(49):31075-85 PMID: 8940103
- 6. Pijpers AHJM et al.. 2001. Verocytotoxin-induced apoptosis of human microvascular endothelial cells.. J Am Soc Nephrol 12(4):767-778 PMID: 11274238
- 7. Hafeez BB et al.. 2006. Green tea polyphenols-induced apoptosis in human osteosarcoma SAOS-2 cells involves a caspase-dependent mechanism with downregulation of nuclear factor-kappaB.. Toxicol Appl Pharmacol 216(1):11-9 PMID: 16797629
- 8. Ingallinella P et al.. 1998. Potent peptide inhibitors of human hepatitis C virus NS3 protease are obtained by optimizing the cleavage products.. Biochemistry 37(25):8906-14 PMID: 9636032
