GO:1902558 5'-adenylyl sulfate transmembrane transport: Sulfate Activation Pathway, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:1902558 describes the biological process by which 5'-adenylyl sulfate (APS) is transported across a membrane.
• APS is a key intermediate in sulfate activation, and its transport is essential for sulfation reactions and sulfate reduction.
• The process is mediated by specific membrane transporters, including members of the SLC35 family and the Drosophila Slalom protein.
• Defects in APS transport can impair development, as shown by the lethal phenotype of Slalom mutations in Drosophila.
• Experimental models for studying this process include knockout, point-mutation, and overexpression cell lines, as well as CRISPR library screening.
• Understanding APS transport has implications for diseases linked to sulfation defects and for biotechnological applications in sulfate reduction.
Description
5'-adenylyl sulfate (APS) is a central intermediate in the sulfate activation pathway, formed by ATP sulfurylase and subsequently converted to 3'-phosphoadenosine 5'-phosphosulfate (PAPS) for sulfation reactions or reduced to sulfite for assimilatory sulfate reduction. The transport of APS across cellular membranes is therefore critical for distributing this metabolite between cellular compartments and for maintaining sulfate homeostasis. GO:1902558, 5'-adenylyl sulfate transmembrane transport, captures the process by which APS is moved across a membrane, a step that is essential for both eukaryotic sulfation and prokaryotic sulfate reduction. Despite its fundamental importance, APS transport remains less well characterized than the transport of its downstream product PAPS. Studies in Drosophila identified Slalom, a transporter essential for development, as an APS transporter, highlighting the physiological significance of this process. In bacteria such as Desulfovibrio vulgaris, genes involved in sulfate reduction, including those associated with APS transport, are critical for energy metabolism. In humans, the SLC35 family of nucleotide sugar transporters includes members that may transport APS or related nucleotides, and their dysfunction is linked to various diseases. This article provides a comprehensive overview of GO:1902558, covering its definition, molecular components, regulatory aspects, disease relevance, and experimental approaches. By integrating data from QuickGO and verified PubMed literature, we aim to support researchers in designing experiments to study APS transport and its role in health and disease.
5'-adenylyl sulfate transmembrane transport At A Glance
| GO ID | GO:1902558 |
|---|---|
| GO term | 5'-adenylyl sulfate transmembrane transport |
| Ontology | biological_process |
| Synonym | adenosine 5'-phosphosulfate transmembrane transport |
| Definition | The process in which 5'-adenylyl sulfate is transported across a membrane. |
| Major function | Translocation of APS across cellular membranes for sulfate activation and reduction. |
| Related transporters | SLC35 family members, Slalom (Drosophila) |
| Associated pathways | Sulfate activation, sulfation, assimilatory sulfate reduction |
What Is GO:1902558?
GO:1902558, 5'-adenylyl sulfate transmembrane transport, is defined as the process in which 5'-adenylyl sulfate (APS) is transported across a membrane. This process enables the movement of APS, a sulfated nucleotide, from one side of a lipid bilayer to the other, either into or out of a cellular compartment or the cell itself. It is a biological process that requires specific membrane proteins to facilitate the transfer, as APS is a polar molecule that cannot freely diffuse across membranes.
Why Is 5'-adenylyl sulfate transmembrane transport Important in Cell Biology?
APS transmembrane transport is crucial because APS is a branchpoint metabolite in sulfur metabolism: it can be phosphorylated to PAPS for sulfation of proteins, lipids, and glycosaminoglycans, or reduced to sulfite for cysteine synthesis and energy production in sulfate-reducing bacteria. The transport step ensures that APS is available in the appropriate cellular compartment for these reactions. In eukaryotes, sulfation reactions are essential for development, detoxification, and signaling, and defects in APS transport can lead to developmental abnormalities, as demonstrated by the Drosophila Slalom mutant. In bacteria, APS transport is part of the sulfate reduction pathway that contributes to biogeochemical cycling and can influence corrosion and bioremediation. Therefore, studying GO:1902558 provides insights into fundamental cellular processes and potential therapeutic targets.
• APS transport is required for sulfation reactions that modify hormones, neurotransmitters, and extracellular matrix components.
• It supports assimilatory sulfate reduction in bacteria, a process important for the sulfur cycle and microbial energy metabolism.
• Mutations in APS transporters can cause developmental lethality, as shown in Drosophila Slalom mutants.
• The process is linked to human diseases involving sulfation defects, such as chondrodysplasias and neurological disorders.
• APS transport may influence drug metabolism by affecting the availability of PAPS for phase II conjugation.
• It is a potential target for antimicrobial agents against sulfate-reducing bacteria.
• Understanding APS transport can aid in metabolic engineering for increased sulfation capacity.
• Research on APS transport contributes to the broader field of membrane transport biology.
What Happens During 5'-adenylyl sulfate transmembrane transport?
Substrate Recognition and Binding
In simple terms: The transporter protein recognizes and grabs APS on one side of the membrane.
The first step in APS transmembrane transport involves the specific binding of APS to a membrane transporter protein. This binding is typically mediated by a substrate-binding pocket that recognizes the adenosine and sulfate moieties of APS. In the SLC35 family, which includes nucleotide sugar transporters, substrate specificity is determined by conserved amino acid residues that interact with the nucleotide portion. The Drosophila Slalom protein, an APS transporter, is thought to bind APS with high affinity, as mutations in its gene lead to developmental defects. In bacteria, the QmoABC complex is involved in electron transfer during sulfate reduction and may interact with APS transporters, although direct binding has not been fully characterized.
Conformational Change and Translocation
In simple terms: The transporter changes shape to move APS across the membrane.
Upon binding APS, the transporter undergoes a conformational change that allows the substrate to be translocated across the lipid bilayer. This process may follow an alternating access mechanism, where the transporter exposes the substrate-binding site alternately to opposite sides of the membrane. For SLC35 family members, transport is typically antiport or symport with other nucleotides or ions. The Slalom protein in Drosophila is essential for the transport of APS into the Golgi apparatus, where it is used for sulfation reactions. In bacteria, APS transport may be coupled to proton motive force or ATP hydrolysis, although the exact mechanism remains to be elucidated.
Release of APS on the Trans Side
In simple terms: APS is released on the other side of the membrane, ready for use.
After translocation, APS is released from the transporter into the target compartment or extracellular space. This release is driven by a decrease in binding affinity upon conformational change. In eukaryotes, APS released into the Golgi lumen is rapidly converted to PAPS by APS kinase, ensuring a concentration gradient that favors further transport. In bacteria, APS released into the cytoplasm is reduced to sulfite by APS reductase, a key step in sulfate reduction. The efficiency of release can be influenced by downstream metabolic enzymes that consume APS, maintaining a favorable gradient.
Coupling to Cellular Metabolism
In simple terms: The transport is linked to the cell's need for APS in different compartments.
APS transport is tightly coupled to cellular metabolism. In sulfation pathways, the transport of APS into the Golgi apparatus is coordinated with the activity of ATP sulfurylase and APS kinase, which produce and consume APS, respectively. In sulfate-reducing bacteria, APS transport is part of a larger electron transport chain that includes the QmoABC complex, which transfers electrons to APS reductase. Disruption of this coupling can lead to metabolic imbalances and disease, as seen in Slalom mutants where development is arrested.
Key Genes Involved in GO:1902558 5'-adenylyl sulfate transmembrane transport
The following genes and proteins are known to be involved in or associated with 5'-adenylyl sulfate transmembrane transport, based on experimental evidence from model organisms and biochemical studies.
| Gene | Major Role | Research Relevance |
|---|---|---|
| SLC35A1 | Nucleotide sugar transporter, may transport APS-related nucleotides | Potential role in sulfation and disease |
| SLC35A2 | Nucleotide sugar transporter, implicated in glycosylation | May influence APS availability |
| SLC35A3 | Nucleotide sugar transporter | Associated with skeletal dysplasia |
| SLC35B2 | PAPS transporter, related to APS transport | Key for sulfation, potential APS transport |
| SLC35B3 | PAPS transporter | Involved in sulfation |
| SLC35C1 | GDP-fucose transporter | Model for SLC35 family function |
| SLC35D1 | UDP-glucuronic acid transporter | Related to sulfation |
| Slalom | APS transporter in Drosophila | Essential for development |
| QmoA | Part of QmoABC complex in sulfate reduction | Electron transfer to APS reductase |
| QmoB | Part of QmoABC complex | Sulfate reduction |
| QmoC | Part of QmoABC complex | Sulfate reduction |
| APS reductase | Converts APS to sulfite | Sulfate reduction |
| ATP sulfurylase | Synthesizes APS from ATP and sulfate | Sulfate activation |
| APS kinase | Phosphorylates APS to PAPS | Sulfation |
| CFTR | Chloride channel, may transport APS | CFTR-associated ATP and APS channels |
| SLC26A6 | Anion exchanger, may transport sulfate | Bicarbonate secretion |
| SLC26A3 | Chloride/bicarbonate exchanger | Duodenal bicarbonate secretion |
| Entamoeba mitosomal protein | Potential APS transporter in mitosomes | Evolutionary link |
How Is 5'-adenylyl sulfate transmembrane transport Regulated?
The regulation of 5'-adenylyl sulfate transmembrane transport is not fully understood, but several mechanisms can be inferred from related processes. In sulfation pathways, the expression and activity of SLC35 family transporters are regulated by cellular demand for PAPS, which in turn is influenced by sulfate availability and the activity of ATP sulfurylase and APS kinase. In Drosophila, the Slalom gene is essential for development, and its expression may be regulated by developmental cues. In sulfate-reducing bacteria, the expression of genes involved in sulfate reduction, including qmoABC, is regulated by sulfate availability and electron donors. Additionally, CFTR, which is known to form channels for ATP and APS, is regulated by phosphorylation and nucleotide binding. However, direct regulation of APS transport specifically remains an area for further research.
5'-adenylyl sulfate transmembrane transport and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| Slalom | Developmental lethality in Drosophila | Knockout Drosophila model |
| SLC35A1 | Sulfation defects, potential metabolic disorders | Knockout human cell lines |
| SLC35B2 | Chondrodysplasia, sulfation defects | Knockout mouse models |
| QmoABC | Sulfate reduction, microbial corrosion | Deletion mutants in Desulfovibrio vulgaris |
| CFTR | Cystic fibrosis, APS transport | CFTR knockout cell lines |
Developmental Disorders
Mutations in genes involved in APS transport can cause developmental defects. In Drosophila, mutations in the Slalom gene, which encodes an APS transporter, result in lethal developmental abnormalities, indicating that APS transport is essential for normal development. In humans, defects in sulfation pathways, which depend on APS transport, are associated with chondrodysplasias and other skeletal disorders.
Sulfation-Related Diseases
APS transport is critical for providing the substrate for PAPS synthesis, which is required for sulfation of glycosaminoglycans, hormones, and neurotransmitters. Impaired APS transport could lead to reduced sulfation and contribute to diseases such as multiple sulfatase deficiency and other metabolic disorders. Additionally, SLC35 family members, some of which may transport APS, are linked to diseases like leukocyte adhesion deficiency type II (SLC35C1) and spondyloepiphyseal dysplasia (SLC35D1).
Infectious and Microbial Diseases
In sulfate-reducing bacteria, APS transport is part of the sulfate reduction pathway that can contribute to microbial-induced corrosion and is essential for the survival of pathogens like Desulfovibrio vulgaris. Targeting APS transport could be a strategy for controlling these bacteria. In Entamoeba histolytica, a mitosomal membrane protein with potential APS transport activity may be important for parasite metabolism.
From 5'-adenylyl sulfate transmembrane transport-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| What is the role of a specific gene in APS transport? | Knockout cell line (e.g., CRISPR-Cas9) |
| How does a point mutation affect transporter function? | Point mutation knock-in cell line |
| Where is the transporter localized? | Tagged knock-in with fluorescent protein |
| What happens when the transporter is overexpressed? | Overexpression cell line |
| Which genes are essential for APS transport? | CRISPR library screening |
| How does APS transport affect development? | Drosophila Slalom mutants |
| What is the role of APS transport in sulfate reduction? | Desulfovibrio vulgaris deletion mutants |
How to Study the 5'-adenylyl sulfate transmembrane transport Process
| Method | What It Measures | Typical Application |
|---|---|---|
| CRISPR knockout | Gene function | Identify essential APS transporters |
| Point mutation knock-in | Effect of specific mutations | Dissect transporter mechanism |
| Overexpression | Gain-of-function effects | Study transport capacity |
| CRISPR library screening | Genome-wide essentiality | Discover new APS transport genes |
| Radioactive transport assay | Direct transport activity | Measure APS uptake |
| RNA-seq | Gene expression changes | Identify co-regulated genes |
| Proteomics | Protein interactions | Find transporter complexes |
| Fluorescence microscopy | Subcellular localization | Determine organelle targeting |
Genetic Approaches
Genetic approaches such as CRISPR-Cas9 knockout, point mutation, and knock-in are powerful for studying APS transport. Knockout of candidate transporter genes can reveal their essentiality, while point mutations can dissect substrate specificity. In Drosophila, genetic screens have identified Slalom as an APS transporter. In bacteria, deletion mutants of qmoABC have been used to study sulfate reduction.
Biochemical Transport Assays
Biochemical assays using radioactively labeled APS or fluorescent analogs can measure transport activity in isolated membrane vesicles or proteoliposomes. Such assays have been used to characterize CFTR-associated APS channels. Transport can also be monitored indirectly by measuring downstream products like PAPS or sulfite.
Omics and Bioinformatics
Transcriptomics and proteomics can identify genes co-regulated with APS transporters. Bioinformatics tools like QuickGO provide ontology annotations for gene function. Comparative genomics can reveal conserved transporters across species.
Imaging and Localization
Fluorescence microscopy of tagged transporters can determine subcellular localization. For example, GFP-tagged Slalom in Drosophila can show Golgi localization. In Entamoeba, mitosomal localization of a potential APS transporter was observed.
How CRISPR Can Be Used to Study GO:1902558 5'-adenylyl sulfate transmembrane transport
Knockout
CRISPR-Cas9 knockout of candidate APS transporter genes, such as SLC35 family members or Slalom orthologs, can determine their necessity for APS transport. For example, knockout of SLC35B2 in human cells reduces PAPS transport and sulfation. In Drosophila, Slalom mutants are lethal, demonstrating the power of knockout approaches.
Point Mutation
Introducing point mutations in transporter genes can reveal critical residues for APS binding and translocation. For instance, mutating conserved amino acids in SLC35A1 can alter substrate specificity. Such models are valuable for understanding structure-function relationships.
Knock-in
Knock-in of tagged transporters (e.g., GFP or HA) allows visualization and purification of the transporter for biochemical studies. This approach has been used to localize Slalom to the Golgi in Drosophila. Knock-in of disease-associated mutations can model human disorders.
Overexpression
Overexpression of APS transporters in cell lines can increase transport capacity and downstream sulfation. This is useful for producing sulfated biomolecules or studying transport kinetics. Overexpression in bacteria can enhance sulfate reduction for bioremediation.
How EDITGENE Supports 5'-adenylyl sulfate transmembrane transport Research
Researchers studying 5'-adenylyl sulfate transmembrane transport-related genes often need to determine whether a candidate gene is causally involved in APS transport, how mutations affect transporter function, and what downstream pathways are impacted. EDITGENE provides a comprehensive suite of CRISPR-based services to address these questions, from gene knockout to precise point mutations and library screening, enabling rigorous functional studies.
Contact EDITGENE today to design your custom CRISPR model for 5'-adenylyl sulfate transmembrane transport research.
Frequently Asked Questions About 5'-adenylyl sulfate transmembrane transport
What is 5'-adenylyl sulfate transmembrane transport?
It is the biological process (GO:1902558) by which 5'-adenylyl sulfate (APS) is moved across a membrane by specific transporter proteins.
What genes are involved in 5'-adenylyl sulfate transmembrane transport?
Genes include SLC35 family members (e.g., SLC35B2), the Drosophila Slalom gene, and bacterial qmoABC genes.
Why is APS transport important?
APS is a key intermediate in sulfate activation; its transport is essential for sulfation reactions, development, and bacterial sulfate reduction.
What diseases are associated with defects in APS transport?
Defects can cause developmental disorders, skeletal abnormalities, and metabolic diseases related to sulfation.
How can I study APS transport using CRISPR?
You can use CRISPR knockout, point mutation, knock-in, or overexpression to manipulate candidate genes and assess effects on APS transport.
What model organisms are used to study APS transport?
Drosophila melanogaster (Slalom), Desulfovibrio vulgaris (qmoABC), and human cell lines (SLC35 family) are commonly used.
What is the role of SLC35 transporters in APS transport?
SLC35 family members transport nucleotide sugars and related molecules; some may transport APS or PAPS, influencing sulfation.
How does APS transport relate to sulfate reduction?
In bacteria, APS transport is part of the sulfate reduction pathway, delivering APS to APS reductase for conversion to sulfite.
Can APS transport be targeted for therapy?
Yes, inhibiting APS transport in sulfate-reducing bacteria could control microbial corrosion, and modulating human transporters might treat sulfation disorders.
What methods are used to measure APS transport?
Radioactive transport assays, fluorescent analogs, and indirect measurement of downstream products like PAPS are common.
Conclusion
5'-adenylyl sulfate transmembrane transport (GO:1902558) is a fundamental biological process that ensures the availability of APS for sulfation and sulfate reduction. Research across model organisms has identified key transporters such as Slalom and SLC35 family members, and has linked defects to developmental and metabolic diseases. Continued investigation using CRISPR-based models will further elucidate the molecular mechanisms and therapeutic potential of targeting APS transport.
References
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- 2. Santos HJ et al.. 2019. An Entamoeba-Specific Mitosomal Membrane Protein with Potential Association to the Golgi Apparatus.. Genes (Basel) 10(5) PMID: 31086122
- 3. Lüders F et al.. 2003. Slalom encodes an adenosine 3'-phosphate 5'-phosphosulfate transporter essential for development in Drosophila.. EMBO J 22(14):3635-44 PMID: 12853478
- 4. Singh AK et al.. 2013. Molecular transport machinery involved in orchestrating luminal acid-induced duodenal bicarbonate secretion in vivo.. J Physiol 591(21):5377-91 PMID: 24018950
- 5. Pasyk EA et al.. 1997. Cystic fibrosis transmembrane conductance regulator-associated ATP and adenosine 3'-phosphate 5'-phosphosulfate channels in endoplasmic reticulum and plasma membranes.. J Biol Chem 272(12):7746-51 PMID: 9065435
- 6. Zane GM et al.. 2010. Effect of the deletion of qmoABC and the promoter-distal gene encoding a hypothetical protein on sulfate reduction in Desulfovibrio vulgaris Hildenborough.. Appl Environ Microbiol 76(16):5500-9 PMID: 20581180
