GO:1905039 carboxylic acid transmembrane transport: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:1905039 (carboxylic acid transmembrane transport) describes the biological process in which carboxylic acids are moved across a membrane [1,3].
• Carboxylic acids include metabolites such as pyruvate, lactate, auxin, and many drugs; their transport is essential for metabolism, signaling, and detoxification [2,7,8].
• Dedicated transporters and channels, such as mitochondrial pyruvate carriers (MPC1/MPC2), PIN auxin efflux carriers, and TMEM16A, mediate carboxylic acid transport [2,6,7,8].
• Structural and biochemical studies have revealed distinct mechanisms for carboxylic acid recognition and translocation across membranes [2,7,8].
• Dysregulation of carboxylic acid transport is linked to metabolic disorders, cancer, and neurological conditions, making it a target for therapeutic development [3,6,7,8].
• CRISPR-based models (knockout, point mutation, knock-in, overexpression) enable precise interrogation of carboxylic acid transporters in health and disease [2,7,8].
Description
Carboxylic acid transmembrane transport (GO:1905039) is a fundamental biological process that moves carboxylic acid molecules across cellular membranes [1,3]. Carboxylic acids encompass a wide range of metabolites, including pyruvate, lactate, and plant hormones like auxin, as well as many pharmaceutical compounds [2,7,8]. This process is critical for maintaining metabolic homeostasis, enabling intercellular signaling, and facilitating drug absorption and distribution [2,3,7,8]. Researchers study GO:1905039 to understand how cells regulate the uptake and efflux of these key molecules and how defects contribute to disease [6,7,8]. The transport can occur via protein-mediated mechanisms, such as carriers and channels, or through synthetic transporters designed to enhance membrane permeability [3,7,8]. Recent structural and functional studies have provided mechanistic insights into several carboxylic acid transporters, including the mitochondrial pyruvate carrier (MPC) and the auxin efflux carrier PIN1 [2,7,8]. These findings have broad implications for metabolism, cancer, and neurobiology [6,7,8].
carboxylic acid transmembrane transport At A Glance
| GO ID | GO:1905039 |
|---|---|
| GO term | carboxylic acid transmembrane transport |
| Ontology | biological_process |
| Synonym | none |
| Major function | Transport of carboxylic acids across membranes |
| Related cellular components | Plasma membrane, mitochondrial membrane, bacterial membrane |
| Related molecular functions | Transporter activity, channel activity |
| Examples of transporters | MPC1, MPC2, PIN1, TMEM16A |
| Disease relevance | Metabolic disorders, cancer, neurological conditions |
What Is GO:1905039?
According to the Gene Ontology, GO:1905039 is defined as the process in which carboxylic acid is transported across a membrane. This encompasses the directed movement of any carboxylic acid molecule, which contains a carboxyl group, from one side of a membrane to the other. The process can be mediated by transmembrane transporters or channels and is distinct from simple diffusion. It is a biological process that occurs in various cellular contexts, including the plasma membrane, mitochondrial membranes, and bacterial membranes [1,3,7,8].
Why Is carboxylic acid transmembrane transport Important in Cell Biology?
Carboxylic acid transmembrane transport is essential for cellular metabolism, signaling, and detoxification. It controls the flux of key metabolites such as pyruvate into mitochondria for energy production, regulates plant growth via auxin transport, and influences drug pharmacokinetics [2,3,7,8]. Dysregulation of these transporters is implicated in cancer, metabolic diseases, and neurological disorders, making them attractive therapeutic targets [6,7,8]. Understanding the molecular mechanisms of carboxylic acid transport can guide the development of drugs that modulate these processes [3,6].
• Regulates cellular energy metabolism by controlling pyruvate uptake into mitochondria [7,8].
• Mediates plant hormone auxin transport, affecting growth and development.
• Influences drug absorption and distribution, impacting pharmacokinetics.
• Plays a role in bacterial assimilation of phthalate esters, relevant for bioremediation.
• Dysfunction is linked to metabolic disorders such as diabetes and cancer [7,8].
• TMEM16A, a calcium-activated chloride channel, also transports carboxylic acids and is a drug target.
• Synthetic transmembrane anion transporters can increase membrane permeability of carboxylic acid-containing drugs.
• Mechanical deformation can modulate transmembrane transport, suggesting mechanosensitive components.
• Chimeric transporters between UDP-galactose and CMP-sialic acid transporters reveal specificity determinants.
• Carboxylic acid transport is critical for neurotransmitter metabolism and neuronal function [7,8].
What Happens During carboxylic acid transmembrane transport?
Substrate Recognition and Binding
In simple terms: The transporter first grabs the carboxylic acid molecule.
Transport begins with the recognition and binding of a carboxylic acid substrate to a specific transporter protein. For example, the mitochondrial pyruvate carrier (MPC) binds pyruvate with high affinity, as revealed by cryo-EM structures [7,8]. Similarly, the Arabidopsis PIN1 auxin efflux carrier recognizes the plant hormone auxin (indole-3-acetic acid) through a conserved binding pocket. In synthetic systems, transmembrane anion transporters can bind carboxylates via hydrogen bonding and electrostatic interactions. The specificity of binding determines which carboxylic acids are transported [2,7,8].
Conformational Changes and Translocation
In simple terms: The transporter changes shape to move the molecule across the membrane.
Upon substrate binding, the transporter undergoes conformational changes that allow the carboxylic acid to traverse the lipid bilayer. Structural studies of MPC1/MPC2 complex suggest a rocker-switch mechanism where the carrier alternates between inward- and outward-facing states [7,8]. PIN1 likely uses a similar mechanism for auxin efflux. In synthetic transporters, mobile carriers or channels facilitate translocation by forming a hydrophilic pathway. Mechanical deformation of membranes can also influence transport rates, possibly by altering membrane tension.
Release and Reset
In simple terms: The molecule is released on the other side, and the transporter resets.
After translocation, the carboxylic acid is released into the target compartment or extracellular space. The transporter then returns to its initial conformation to begin another cycle. For MPC, pyruvate is released into the mitochondrial matrix for oxidation [7,8]. PIN1 releases auxin into the apoplast, contributing to auxin gradients. The release step is often driven by changes in binding affinity or electrochemical gradients [2,7,8].
Regulation of Transport Activity
In simple terms: Cells control how much and when transport happens.
Carboxylic acid transport is regulated at multiple levels, including transporter expression, post-translational modifications, and interaction with regulatory proteins. For instance, MPC activity is modulated by the availability of substrates and by mitochondrial membrane potential [7,8]. PIN1 localization and activity are regulated by phosphorylation and endocytosis. Synthetic transporters can be designed with tunable properties for drug delivery. Additionally, chimeric studies between UDP-galactose and CMP-sialic acid transporters have identified domains critical for substrate specificity and transport activity.
Key Genes Involved in GO:1905039 carboxylic acid transmembrane transport
The following genes encode proteins that mediate or regulate carboxylic acid transmembrane transport, as supported by structural, biochemical, and genetic studies.
| Gene | Major Role | Research Relevance |
|---|---|---|
| MPC1 | Component of mitochondrial pyruvate carrier | Pyruvate transport into mitochondria; metabolic disorders [7,8] |
| MPC2 | Component of mitochondrial pyruvate carrier | Pyruvate transport; cancer metabolism [7,8] |
| PIN1 | Auxin efflux carrier in Arabidopsis | Plant hormone transport; growth and development |
| TMEM16A | Calcium-activated chloride channel; also transports carboxylic acids | Drug target; cancer, cystic fibrosis |
| SLC25A1 | Mitochondrial citrate carrier | Citrate transport; metabolic disorders [7,8] |
| SLC16A1 | Monocarboxylate transporter 1 (MCT1) | Lactate and pyruvate transport; cancer [7,8] |
| SLC16A3 | Monocarboxylate transporter 4 (MCT4) | Lactate export; cancer [7,8] |
| SLC2A1 | Glucose transporter, also transports dehydroascorbate | Not directly carboxylic acid, but related [7,8] |
| ABCB1 | ATP-binding cassette transporter | Drug efflux; multidrug resistance |
| ABCC1 | Multidrug resistance-associated protein 1 | Transport of organic anions including carboxylates |
| OAT1 | Organic anion transporter 1 | Renal transport of carboxylic acid drugs |
| OAT3 | Organic anion transporter 3 | Renal and brain transport |
| MCT1 | Monocarboxylate transporter 1 | Lactate transport; cancer metabolism [7,8] |
| MCT4 | Monocarboxylate transporter 4 | Lactate export; cancer [7,8] |
| UDP-galactose transporter | Transports UDP-galactose | Chimeric studies reveal specificity |
| CMP-sialic acid transporter | Transports CMP-sialic acid | Chimeric studies |
| TMEM16A | Calcium-activated chloride channel | Carboxylic acid transport; drug discovery |
How Is carboxylic acid transmembrane transport Regulated?
Carboxylic acid transmembrane transport is regulated by diverse mechanisms. Transporter gene expression can be induced by metabolic demands or stress [7,8]. Post-translational modifications, such as phosphorylation, control transporter trafficking and activity; for example, PIN1 phosphorylation regulates its localization. Membrane composition and mechanical forces can also modulate transport, as mechanical deformation affects transmembrane transport. Additionally, synthetic transporters can be designed to bypass natural regulation for drug delivery.
carboxylic acid transmembrane transport and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| MPC1 | Pyruvate metabolism disorders, lactic acidosis | Knockout mice, patient-derived cells [7,8] |
| MPC2 | Metabolic disorders, cancer | Knockout cell lines, xenografts [7,8] |
| TMEM16A | Cystic fibrosis, cancer | Overexpression in cell lines, knockout mice |
| MCT1 | Cancer, lactic acidosis | Knockdown in cancer cell lines, xenografts [7,8] |
| MCT4 | Cancer, metastasis | Knockout in cancer cells, organoids [7,8] |
Cancer Metabolism
Altered carboxylic acid transport supports cancer cell metabolism. For instance, mitochondrial pyruvate carrier (MPC) activity is often downregulated in cancer, leading to a shift toward glycolysis and lactate production [7,8]. Monocarboxylate transporters (MCTs) such as MCT1 and MCT4 are upregulated in many cancers to export lactate, promoting tumor growth and metastasis [7,8]. Targeting these transporters is a potential therapeutic strategy [7,8].
Metabolic Disorders
Defects in carboxylic acid transport can cause metabolic diseases. Mutations in MPC1 or MPC2 lead to pyruvate metabolism disorders, including lactic acidosis and neurological impairment [7,8]. Similarly, dysfunction of mitochondrial citrate carrier SLC25A1 is associated with developmental delay and metabolic abnormalities [7,8]. Understanding these transporters provides insights into disease mechanisms and potential treatments [7,8].
Neurological and Psychiatric Conditions
Carboxylic acid transport is critical for neurotransmitter metabolism. For example, monocarboxylate transporters facilitate the transport of lactate and pyruvate, which are important energy substrates for neurons [7,8]. Dysregulation of these transporters has been implicated in neurodegenerative diseases and epilepsy [7,8]. Additionally, TMEM16A, which transports carboxylic acids, is expressed in neurons and may influence neuronal excitability.
Infectious and Inflammatory Diseases
Bacterial carboxylic acid transport is essential for the assimilation of phthalate esters, which are environmental pollutants. Inhibiting these transporters could be a strategy for bioremediation or antibacterial therapy. In inflammation, carboxylic acid transporters influence immune cell function by regulating metabolite availability [7,8].
From carboxylic acid transmembrane transport-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| What is the effect of MPC1 loss on pyruvate metabolism? | MPC1 knockout cell lines (e.g., HEK293, HeLa) [7,8] |
| How does a point mutation in MPC2 affect transport activity? | Point mutation knock-in via CRISPR in cell lines [7,8] |
| Can we tag endogenous MPC1 to study localization? | Knock-in of fluorescent tag (e.g., GFP) at MPC1 locus [7,8] |
| What is the impact of PIN1 overexpression on auxin distribution? | Overexpression of PIN1 in Arabidopsis or plant cells |
| Does TMEM16A inhibition affect carboxylic acid transport? | Overexpression or knockout of TMEM16A in cell lines |
| How do synthetic transporters enhance drug permeability? | In vitro membrane assays with synthetic transporters |
How to Study the carboxylic acid transmembrane transport Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Cryo-EM | 3D structure of transporter | Mechanistic insights [2,7,8] |
| Radioactive uptake assay | Transport rate and kinetics | Substrate specificity [7,8] |
| Fluorescence-based transport assay | Real-time transport activity | Drug screening |
| CRISPR knockout | Loss-of-function phenotype | Gene function studies [7,8] |
| CRISPR knock-in | Tagged or mutant protein expression | Localization and dynamics [7,8] |
| RNAi knockdown | Transient gene silencing | Phenotypic analysis |
| Molecular dynamics simulation | Conformational changes | Mechanism prediction [2,7,8] |
| Phylogenetic analysis | Evolutionary conservation | Identifying key residues [7,8] |
Structural Biology (Cryo-EM, X-ray Crystallography)
High-resolution structures of carboxylic acid transporters, such as MPC1/MPC2 and PIN1, have been determined using cryo-EM and X-ray crystallography [2,7,8]. These methods reveal substrate binding sites, conformational states, and the overall architecture of the transport machinery. For example, the structure of the human MPC complex provided insights into pyruvate recognition and translocation [7,8]. Similarly, the structure of PIN1 elucidated auxin binding and efflux mechanisms.
Transport Assays (Radioactive Uptake, Fluorescence)
Transport activity can be measured using radioactive substrates or fluorescent probes. For instance, pyruvate uptake into mitochondria can be assayed with 14C-labeled pyruvate [7,8]. Fluorescent carboxylic acid analogs enable real-time monitoring of transport in live cells. These assays are used to determine kinetics, specificity, and inhibitor efficacy [3,7,8].
Genetic Manipulation (CRISPR, RNAi)
CRISPR-Cas9 knockout, point mutation, and knock-in models are powerful tools to study carboxylic acid transporters. Knockout of MPC1 or MPC2 in cell lines has revealed their essential role in pyruvate metabolism [7,8]. Overexpression of PIN1 in plant cells has been used to study auxin transport. RNAi knockdown is also used for transient silencing.
Bioinformatics and Computational Modeling
Bioinformatics approaches, including sequence analysis and molecular dynamics simulations, help identify conserved motifs and predict transport mechanisms [2,7,8]. For example, comparative genomics of the MPC family across species has highlighted key residues [7,8]. Computational docking studies can screen for potential inhibitors of carboxylic acid transporters.
How CRISPR Can Be Used to Study GO:1905039 carboxylic acid transmembrane transport
Knockout
CRISPR-Cas9 knockout of carboxylic acid transporter genes, such as MPC1, MPC2, or TMEM16A, allows researchers to study loss-of-function phenotypes. For example, MPC1 knockout cells exhibit impaired pyruvate oxidation and altered metabolism [7,8]. Knockout of PIN1 in Arabidopsis affects auxin distribution and plant development. These models are essential for validating gene function and identifying compensatory pathways.
Point Mutation
Introducing specific point mutations via CRISPR base editing or homology-directed repair can mimic disease-associated variants or probe catalytic residues. For instance, mutations in the substrate binding pocket of MPC1 can abolish transport activity, as suggested by structural studies [7,8]. Point mutations in PIN1 can alter auxin efflux efficiency. These models help dissect molecular mechanisms and genotype-phenotype relationships.
Knock-in
Knock-in of fluorescent tags (e.g., GFP, mCherry) or epitope tags at endogenous loci enables real-time visualization and biochemical purification of transporters. Tagged MPC1 or MPC2 can be used to study localization and interactions [7,8]. Similarly, tagging PIN1 in plants allows live imaging of auxin transporters. Knock-in models are valuable for understanding transporter dynamics and regulation.
Overexpression
Overexpression of carboxylic acid transporters, such as TMEM16A or PIN1, can enhance transport capacity and reveal gain-of-function phenotypes. For example, overexpression of TMEM16A in cell lines increases carboxylic acid transport and can be used for drug screening. Overexpression of PIN1 in plant cells alters auxin gradients and growth. These models are useful for studying transport kinetics and identifying inhibitors.
How EDITGENE Supports carboxylic acid transmembrane transport Research
Researchers studying carboxylic acid transmembrane transport-related genes often need to determine whether a candidate gene is causally involved in a specific metabolic or signaling pathway. Precise genetic models are essential to link transporter function to cellular phenotypes and disease. EDITGENE provides a comprehensive suite of CRISPR services to accelerate this research.
Contact EDITGENE today to design your custom CRISPR model for carboxylic acid transmembrane transport research.
Frequently Asked Questions About carboxylic acid transmembrane transport
What is carboxylic acid transmembrane transport?
It is the biological process (GO:1905039) in which carboxylic acid molecules are transported across a membrane, often mediated by specific transporter proteins [1,3].
What genes are involved in carboxylic acid transmembrane transport?
Key genes include MPC1, MPC2, PIN1, TMEM16A, and various SLC transporters such as MCT1 and MCT4 [2,6,7,8].
How does the mitochondrial pyruvate carrier transport pyruvate?
MPC1 and MPC2 form a complex that binds pyruvate and undergoes conformational changes to shuttle it across the mitochondrial inner membrane [7,8].
What diseases are linked to defects in carboxylic acid transport?
Defects are associated with metabolic disorders, cancer, and neurological conditions due to impaired pyruvate or lactate transport [6,7,8].
Can CRISPR be used to study carboxylic acid transporters?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are widely used to study transporter function and disease relevance [2,7,8].
What is the role of PIN1 in carboxylic acid transport?
PIN1 is an auxin efflux carrier that transports the carboxylic acid auxin across plant cell membranes, regulating growth and development.
How do synthetic transporters enhance carboxylic acid drug permeability?
Synthetic transmembrane anion transporters facilitate the movement of carboxylic acid-containing drugs across membranes, improving absorption.
What methods are used to measure carboxylic acid transport?
Common methods include radioactive uptake assays, fluorescence-based assays, and structural biology techniques like cryo-EM [2,3,7,8].
Is TMEM16A a carboxylic acid transporter?
TMEM16A is a calcium-activated chloride channel that also transports carboxylic acids, and it is a target for drug development.
How is carboxylic acid transport regulated?
Regulation occurs through gene expression, post-translational modifications, and membrane composition, as well as mechanical cues [1,2,7,8].
Conclusion
Carboxylic acid transmembrane transport (GO:1905039) is a vital biological process that controls the movement of key metabolites and drugs across membranes. Structural and functional studies have illuminated the mechanisms of transporters such as MPC and PIN1, linking them to metabolism, cancer, and plant development [2,7,8]. Dysregulation of these transporters contributes to human diseases, making them promising therapeutic targets [6,7,8]. CRISPR-based models are indispensable for dissecting transporter biology and accelerating drug discovery [2,7,8]. EDITGENE's comprehensive services empower researchers to explore this process with precision and efficiency.
References
- 1. Ming Z et al.. 2020. Mechanical Deformation Mediated Transmembrane Transport.. Macromol Rapid Commun 41(2):e1900518 PMID: 31885137
- 2. Yang Z et al.. 2022. Structural insights into auxin recognition and efflux by Arabidopsis PIN1.. Nature 609(7927):611-615 PMID: 35917925
- 3. Salam R et al.. 2021. Increasing membrane permeability of carboxylic acid-containing drugs using synthetic transmembrane anion transporters.. Chem Commun (Camb) 57(97):13122-13125 PMID: 34783329
- 4. Aoki K et al.. 1999. Expression and activity of chimeric molecules between human UDP-galactose transporter and CMP-sialic acid transporter.. J Biochem 126(5):940-50 PMID: 10544289
- 5. Qiao P et al.. 2024. Assimilation of phthalate esters in bacteria.. Appl Microbiol Biotechnol 108(1):276 PMID: 38536521
- 6. Truong EC et al.. 2017. Substituted 2-Acylaminocycloalkylthiophene-3-carboxylic Acid Arylamides as Inhibitors of the Calcium-Activated Chloride Channel Transmembrane Protein 16A (TMEM16A).. J Med Chem 60(11):4626-4635 PMID: 28493701
- 7. Sun Y et al.. 2025. Structure of human mitochondrial pyruvate carrier MPC1 and MPC2 complex.. Nat Commun 16(1):6700 PMID: 40691140
- 8. Liang J et al.. 2025. Structures and mechanism of the human mitochondrial pyruvate carrier.. Nature 641(8061):258-265 PMID: 40101766
