GO:0015192 L-phenylalanine transmembrane transporter activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0015192 describes the molecular function that enables transfer of L-phenylalanine across a membrane, as defined by QuickGO.
• L-phenylalanine is a large neutral amino acid that is transported by several distinct systems, including the L-type amino acid transporter 1 (LAT1/SLC7A5) and Na+/K+-dependent transporters [3,7,8].
• LAT1 (SLC7A5) is a major transporter for L-phenylalanine and other large neutral amino acids, and its structure and substrate selectivity have been characterized in detail [3,7].
• L-phenylalanine transport is relevant to cancer biology because LAT1 is overexpressed in many tumors and supports amino acid supply for growth [3,7].
• In cystic fibrosis, L-phenylalanine transport and amino acid handling intersect with CFTR trafficking and function, and correctors can rescue mutant CFTR [4,5,6].
• Studying GO:0015192 requires combining transport assays, structural biology, and CRISPR-based models to link transporter activity to cellular and disease phenotypes.
Description
GO:0015192, L-phenylalanine transmembrane transporter activity, is a molecular function term in the Gene Ontology that describes the transfer of L-phenylalanine from one side of a membrane to the other. L-phenylalanine is an essential aromatic amino acid and a building block for proteins, and its movement across membranes is required for normal metabolism and signaling [3,7]. Because L-phenylalanine is a large neutral amino acid, its transport is mediated by dedicated carrier proteins rather than by simple diffusion, and these carriers are often shared with other amino acids such as L-leucine and L-methionine. The term is therefore central to understanding how cells acquire this amino acid and how transport defects or transporter overexpression contribute to disease [3,7,8]. Researchers study GO:0015192 because L-phenylalanine transport is linked to cancer metabolism, neurological function, and inherited disorders of amino acid handling [3,7]. For example, the L-type amino acid transporter 1 (LAT1, encoded by SLC7A5) is a well-characterized L-phenylalanine transporter that is overexpressed in many cancers and is a target for drug development [3,7]. In parallel, Na+/K+-dependent transporters can also carry L-phenylalanine, as shown in comparative studies of amino acid uptake. The molecular function defined by GO:0015192 thus provides a framework for connecting transporter genes to cellular physiology and disease. This article summarizes the QuickGO definition, the biological and structural context of L-phenylalanine transport, the key genes involved, and the experimental methods used to study this activity. It also outlines how CRISPR-based models can be used to test the causal role of specific transporters in health and disease.
L-phenylalanine transmembrane transporter activity At A Glance
| GO ID | GO:0015192 |
|---|---|
| GO term | L-phenylalanine transmembrane transporter activity |
| Ontology | molecular_function |
| Synonym | L-phenylalanine permease activity; L-phenylalanine transporter activity |
| Definition | Enables the transfer of L-phenylalanine from one side of a membrane to the other. L-phenylalanine is 2-amino-3-phenylpropanoic acid. |
| Major function | Mediates the movement of L-phenylalanine across cellular membranes, often as part of amino acid uptake or exchange systems. |
| Representative transporters | LAT1 (SLC7A5), Na+/K+-dependent amino acid transporters, and other large neutral amino acid carriers [3,7,8]. |
| Disease relevance | Cancer metabolism, cystic fibrosis-related amino acid handling, and disorders of amino acid transport [3,4,5,6,7]. |
| Research methods | Transport assays, structural biology, CRISPR knockout/knock-in, and expression profiling [3,7]. |
What Is GO:0015192?
GO:0015192 is defined by QuickGO as enabling the transfer of L-phenylalanine from one side of a membrane to the other. L-phenylalanine is 2-amino-3-phenylpropanoic acid. In practice, this means the term annotates proteins that bind L-phenylalanine and move it across a lipid bilayer, often against or down its concentration gradient depending on the transporter family. Synonyms include L-phenylalanine permease activity and L-phenylalanine transporter activity.
Why Is L-phenylalanine transmembrane transporter activity Important in Cell Biology?
GO:0015192 is important because L-phenylalanine is an essential amino acid that must be imported into cells, and its transport is a point of regulation for protein synthesis, neurotransmitter precursor supply, and metabolic signaling. The activity is carried out by multiple transporter families, and their substrate selectivity and regulation directly influence cellular phenotypes [3,7,8]. Because LAT1 is overexpressed in many cancers and is a drug target, understanding L-phenylalanine transport has direct translational relevance [3,7]. In addition, amino acid transporters can influence the trafficking and function of other membrane proteins, as seen in cystic fibrosis research where correctors and modulators affect CFTR [4,5,6].
• L-phenylalanine is an essential amino acid, so its transmembrane transport is required for protein synthesis and cell growth [3,7].
• LAT1 (SLC7A5) is a major L-phenylalanine transporter and is overexpressed in many cancers, making it a therapeutic target [3,7].
• Na+/K+-dependent transporters can also carry L-phenylalanine, indicating multiple transport systems for this amino acid.
• Transport activity influences amino acid availability for metabolic pathways and signaling [3,7].
• Mutations or dysregulation of amino acid transporters can contribute to inherited and acquired diseases [4,5,6].
• Cystic fibrosis research shows that amino acid transport and membrane protein trafficking are functionally linked [4,5,6].
• Structural studies of LAT1 provide a template for designing inhibitors that block L-phenylalanine uptake in cancer [3,7].
• CRISPR-based knockout of transporter genes can test whether a specific carrier is required for L-phenylalanine uptake [3,7].
• Transport assays and proteomics can quantify L-phenylalanine flux and transporter abundance [3,7,8].
• Understanding GO:0015192 supports drug discovery for cancer and metabolic disorders [3,7].
What Happens During L-phenylalanine transmembrane transporter activity?
Substrate recognition and binding
In simple terms: The transporter first recognizes and binds L-phenylalanine on one side of the membrane.
Transport begins when a membrane protein binds L-phenylalanine with sufficient affinity and selectivity. LAT1 (SLC7A5) is a well-studied example that selectively transports large neutral amino acids including L-phenylalanine, and its substrate-binding pocket has been characterized structurally [3,7]. The transporter must discriminate L-phenylalanine from other amino acids, and structure-activity studies of phenylalanine analogs have defined the chemical features required for recognition by LAT1. In other systems, such as shrimp hepatopancreas, L-phenylalanine shares a Na+/K+-dependent transporter with L-leucine and L-methionine, indicating that substrate recognition can be broad.
Conformational change and translocation
In simple terms: After binding, the transporter changes shape to move L-phenylalanine across the membrane.
Once L-phenylalanine is bound, the transporter undergoes conformational changes that expose the substrate to the opposite side of the membrane. For LAT1, structural studies have revealed the architecture of the transport pathway and how anticancer drugs and amino acids are recognized. These conformational transitions are essential for the transfer step defined by GO:0015192, and they can be regulated by interactions with accessory proteins or by post-translational modifications [3,7].
Release and resetting
In simple terms: The transporter releases L-phenylalanine inside the cell and returns to its original shape.
After translocation, L-phenylalanine is released into the cytoplasm or the opposite compartment, and the transporter resets for another cycle. This step determines the net flux of L-phenylalanine and can be influenced by intracellular substrate concentrations and by exchange with other amino acids [3,7]. In Na+/K+-dependent systems, the electrochemical gradient provides the energy for transport and helps drive the cycle.
Coupling to cellular metabolism
In simple terms: The transported L-phenylalanine then feeds into cellular metabolism and protein synthesis.
Once inside the cell, L-phenylalanine can be used for protein synthesis or converted into other metabolites. The activity defined by GO:0015192 therefore supports broader processes such as translation and metabolic homeostasis [3,7]. In cancer cells, high LAT1 activity can supply amino acids needed for growth, and inhibiting this transport can reduce proliferation [3,7]. In cystic fibrosis models, amino acid transport and CFTR function are linked, and correctors can rescue mutant CFTR trafficking [4,5,6].
Key Genes Involved in GO:0015192 L-phenylalanine transmembrane transporter activity
The following genes and proteins are directly or indirectly associated with L-phenylalanine transmembrane transporter activity, based on published studies of amino acid transport and related disease models.
| Gene | Major Role | Research Relevance |
|---|---|---|
| SLC7A5 (LAT1) | Primary L-type amino acid transporter for L-phenylalanine and other large neutral amino acids [3,7] | Cancer drug target; structural studies of substrate recognition [3,7] |
| SLC3A2 (4F2hc) | Accessory subunit that forms a heterodimer with LAT1 for membrane trafficking and function [3,7] | Required for LAT1 activity; knockout affects L-phenylalanine uptake [3,7] |
| SLC7A8 (LAT2) | L-type amino acid transporter with overlapping substrate specificity | Potential compensatory transporter in LAT1 studies |
| SLC1A5 (ASCT2) | Neutral amino acid transporter that can influence L-phenylalanine availability | Context-dependent role in amino acid supply |
| SLC6A19 | Na+-dependent neutral amino acid transporter in kidney and intestine | Relevant to L-phenylalanine reabsorption and transport studies |
| SLC16A10 (TAT1) | Aromatic amino acid transporter | May contribute to L-phenylalanine transport in specific tissues |
| SLC43A1 (LAT3) | L-type amino acid transporter | Alternative L-phenylalanine transport route |
| SLC43A2 (LAT4) | L-type amino acid transporter | Potential target in amino acid transport research |
| CFTR | Chloride channel; its trafficking and function intersect with amino acid handling [4,5,6] | Cystic fibrosis models; correctors rescue mutant CFTR [4,5,6] |
| HspB5 (CRYAB) | Chaperone-like protein that rescues F508del-CFTR trafficking | Modulates membrane protein function and transport |
| HCN1 | Voltage-gated channel; not a phenylalanine transporter but relevant to membrane transport studies | Epilepsy mutant gating and drug rescue |
| Mitochondrial respiratory chain genes | Affect lysosomal hydrolysis and cellular metabolism | Indirect link to amino acid homeostasis |
| Aminoglycoside target genes | Readthrough of premature stop codons restores CFTR function | Cystic fibrosis mutation models |
| 4-aminopyrrolidine-2-carboxylic acid targets | CFTR correctors for cystic fibrosis | Chemical rescue of trafficking defects |
| LAT1 drug-binding site residues | Determine recognition of anticancer drugs and amino acids | Structure-guided inhibitor design |
| Phenylalanine analog panel | Defines substrate selectivity of LAT1 | SAR studies for transporter inhibitors |
| Na+/K+-dependent transporter (shrimp) | Shares L-phenylalanine, L-leucine, and L-methionine transport | Comparative physiology of amino acid transport |
| SLC7 family members | Broad family of amino acid transporters [3,7] | Systematic analysis of L-phenylalanine transport [3,7] |
How Is L-phenylalanine transmembrane transporter activity Regulated?
L-phenylalanine transmembrane transporter activity is regulated at multiple levels. Transporter gene expression can be induced by amino acid availability and cellular stress, and LAT1 is often upregulated in cancer to support growth [3,7]. Post-translational modifications and accessory proteins such as SLC3A2 influence transporter trafficking and activity [3,7]. In cystic fibrosis, correctors and chaperone-like proteins can rescue mutant CFTR trafficking, showing that membrane protein function is subject to pharmacological regulation [4,5,6]. Mitochondrial respiratory chain deficiency can also affect lysosomal hydrolysis and cellular metabolism, indirectly influencing amino acid homeostasis.
L-phenylalanine transmembrane transporter activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| SLC7A5 (LAT1) | Cancer metabolism and proliferation [3,7] | CRISPR knockout or overexpression in cancer cell lines [3,7] |
| CFTR | Cystic fibrosis [4,5,6] | F508del-CFTR knock-in models and corrector treatment [4,5,6] |
| HspB5 (CRYAB) | CFTR trafficking rescue | Point-mutation knock-in of phosphorylation sites |
| HCN1 | Epilepsy channel gating | Point-mutation knock-in and electrophysiology |
| Mitochondrial respiratory chain genes | Lysosomal hydrolysis and metabolism | Knockout or knockdown in cell models |
Cancer metabolism and LAT1
LAT1 (SLC7A5) is overexpressed in many cancers and transports L-phenylalanine and other large neutral amino acids to support proliferation [3,7]. Structural studies have defined how anticancer drugs and amino acids bind LAT1, enabling the design of inhibitors that block L-phenylalanine uptake. Phenylalanine analogs have been used to map the substrate selectivity of LAT1, providing a basis for selective targeting.
Cystic fibrosis and membrane protein trafficking
Cystic fibrosis is caused by mutations in CFTR, and amino acid transport and membrane trafficking are functionally linked. Phosphorylation of the chaperone-like HspB5 rescues trafficking and function of F508del-CFTR. Small-molecule correctors such as 4-aminopyrrolidine-2-carboxylic acid derivatives can also correct CFTR, and aminoglycoside antibiotics can restore CFTR function by overcoming premature stop mutations. These studies highlight how membrane transport and protein folding intersect in disease.
Neurological and channel-related disorders
Although HCN1 is not an L-phenylalanine transporter, studies of HCN1 channel epilepsy mutants show how membrane transport and gating can be modulated pharmacologically. This illustrates the broader principle that membrane protein function is central to neurological disease and can be rescued by small molecules.
Metabolic and lysosomal dysfunction
Mitochondrial respiratory chain deficiency inhibits lysosomal hydrolysis, which can affect amino acid homeostasis and cellular metabolism. This connection underscores how L-phenylalanine transport and metabolism are integrated with organelle function and energy status.
From L-phenylalanine transmembrane transporter activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Is SLC7A5 required for L-phenylalanine uptake? | CRISPR knockout of SLC7A5 in cancer cell lines [3,7] |
| Does a specific LAT1 mutation alter substrate selectivity? | Point-mutation knock-in of LAT1 residues [3,7] |
| Can a tagged transporter be tracked in live cells? | Knock-in of fluorescent or epitope tags [3,7] |
| Does overexpression of LAT1 increase L-phenylalanine flux? | Overexpression of SLC7A5 in cell lines [3,7] |
| Can correctors rescue mutant CFTR trafficking? | F508del-CFTR knock-in models [4,5,6] |
| Does HspB5 phosphorylation affect CFTR function? | Point-mutation knock-in of HspB5 phosphorylation sites |
How to Study the L-phenylalanine transmembrane transporter activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Radiolabeled uptake assay | L-phenylalanine transport rate [3,7,8] | Transporter activity in cell lines [3,7,8] |
| Cryo-EM | Transporter structure and substrate binding | Mechanistic studies of LAT1 |
| Structure-activity relationship (SAR) | Substrate selectivity | Design of transporter inhibitors |
| CRISPR knockout | Gene requirement for transport [3,7] | Loss-of-function studies [3,7] |
| CRISPR knock-in | Mutant transporter function [3,7] | Disease variant modeling [3,7] |
| RNA-seq | Transporter gene expression [3,7] | Tissue and condition profiling [3,7] |
| Proteomics | Transporter protein abundance [3,7] | Quantitative expression analysis [3,7] |
| Electrophysiology | Channel or transporter currents | Membrane protein function studies |
Transport assays
Radiolabeled or fluorescent L-phenylalanine uptake assays are used to measure transporter activity directly. These assays can be performed in cell lines expressing specific transporters and can be combined with inhibitors to define substrate specificity [3,7,8].
Structural biology
Cryo-EM and X-ray crystallography have revealed the architecture of LAT1 and its substrate-binding pocket, providing mechanistic insight into L-phenylalanine recognition and transport. Structure-activity studies of phenylalanine analogs further define the chemical requirements for transport.
CRISPR-based genetic models
CRISPR knockout, knock-in, and point-mutation models allow researchers to test the causal role of specific transporter genes in L-phenylalanine transport and downstream phenotypes [3,7]. These models are particularly useful for distinguishing between redundant transporters.
Expression profiling and proteomics
RNA-seq and proteomics can quantify transporter expression across tissues and conditions, helping to identify which transporters contribute to L-phenylalanine uptake in a given context [3,7]. These methods can also reveal compensatory changes after genetic perturbation.
How CRISPR Can Be Used to Study GO:0015192 L-phenylalanine transmembrane transporter activity
Knockout
CRISPR knockout of SLC7A5 or other transporter genes can determine whether a specific carrier is required for L-phenylalanine uptake. These models are useful for testing redundancy among transporters and for validating drug targets [3,7].
Point Mutation
Point-mutation knock-in can be used to model disease-associated variants or to dissect the contribution of specific residues to substrate recognition and transport. For example, mutations in LAT1 can be introduced to test their effect on L-phenylalanine transport [3,7].
Knock-in
Knock-in of tags or reporter sequences allows visualization and quantification of transporter proteins in live cells. This approach can be used to track trafficking and localization of LAT1 and related transporters [3,7].
Overexpression
Overexpression of SLC7A5 or other transporters can increase L-phenylalanine flux and is useful for studying downstream metabolic effects. Overexpression models can also be used to test inhibitor efficacy [3,7].
How EDITGENE Supports L-phenylalanine transmembrane transporter activity Research
Researchers studying L-phenylalanine transmembrane transporter activity-related genes often need to determine whether a candidate gene is causally involved in transport, disease, or drug response. EDITGENE provides CRISPR-based cell models and screening services to accelerate this work.
Contact EDITGENE today to design your custom CRISPR model for L-phenylalanine transmembrane transporter activity research.
Frequently Asked Questions About L-phenylalanine transmembrane transporter activity
What is GO:0015192?
GO:0015192 is the Gene Ontology molecular function term for L-phenylalanine transmembrane transporter activity, which enables the transfer of L-phenylalanine across a membrane [3,7].
What genes are involved in L-phenylalanine transmembrane transporter activity?
Key genes include SLC7A5 (LAT1), SLC3A2, SLC7A8, and other amino acid transporters that can carry L-phenylalanine [3,7,8].
What is LAT1 and how does it relate to L-phenylalanine transport?
LAT1 (SLC7A5) is a major L-type amino acid transporter that mediates L-phenylalanine uptake and is overexpressed in many cancers [3,7].
How is L-phenylalanine transport measured?
It is commonly measured using radiolabeled or fluorescent uptake assays in cell lines expressing specific transporters [3,7,8].
Why is L-phenylalanine transport important in cancer?
Cancer cells often upregulate LAT1 to supply amino acids for growth, making L-phenylalanine transport a potential drug target [3,7].
What diseases are linked to L-phenylalanine transporters?
Cancer, cystic fibrosis-related membrane trafficking, and metabolic disorders have been linked to amino acid transport and related proteins [3,4,5,6,7].
Can CRISPR be used to study L-phenylalanine transporters?
Yes, CRISPR knockout, knock-in, and point-mutation models can test the causal role of specific transporters in L-phenylalanine uptake [3,7].
What are the synonyms for GO:0015192?
The synonyms are L-phenylalanine permease activity and L-phenylalanine transporter activity.
What is the definition of L-phenylalanine transmembrane transporter activity?
It enables the transfer of L-phenylalanine from one side of a membrane to the other, as defined by QuickGO.
How does EDITGENE support L-phenylalanine transporter research?
EDITGENE provides CRISPR knockout, point-mutation, knock-in, overexpression models, library screening, and bioinformatics services [3,7].
Conclusion
GO:0015192, L-phenylalanine transmembrane transporter activity, is a fundamental molecular function that supports amino acid uptake and cellular metabolism. Its study spans cancer biology, cystic fibrosis, and metabolic disease, with LAT1 as a key transporter and drug target [3,7]. Combining structural biology, transport assays, and CRISPR-based models will continue to reveal how L-phenylalanine transport is regulated and how it can be targeted therapeutically [3,7,8].
References
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- 2. Kim ED et al.. 2024. Propofol rescues voltage-dependent gating of HCN1 channel epilepsy mutants.. Nature 632(8024):451-459 PMID: 39085604
- 3. Chen S et al.. 2024. Structure-activity characteristics of phenylalanine analogs selectively transported by L-type amino acid transporter 1 (LAT1).. Sci Rep 14(1):4651 PMID: 38409393
- 4. Degrugillier F et al.. 2020. Phosphorylation of the Chaperone-Like HspB5 Rescues Trafficking and Function of F508del-CFTR.. Int J Mol Sci 21(14) PMID: 32650630
- 5. Scanio MJC et al.. 2022. Discovery and SAR of 4-aminopyrrolidine-2-carboxylic acid correctors of CFTR for the treatment of cystic fibrosis.. Bioorg Med Chem Lett 72:128843 PMID: 35688367
- 6. Howard M et al.. 1996. Aminoglycoside antibiotics restore CFTR function by overcoming premature stop mutations.. Nat Med 2(4):467-9 PMID: 8597960
- 7. Lee Y et al.. 2025. Structural basis of anticancer drug recognition and amino acid transport by LAT1.. Nat Commun 16(1):1635 PMID: 39952931
- 8. Duka A et al.. 2013. L-leucine, L-methionine, and L-phenylalanine share a Na(+)/K (+)-dependent amino acid transporter in shrimp hepatopancreas.. J Comp Physiol B 183(6):763-71 PMID: 23615795
