# GABRR3 Gene: Structure, Function, and Clinical Significance ## Key Takeaways - GABRR3 encodes a subunit of GABAC receptors, which are pentameric chloride channels mediating fast inhibitory neurotransmission, primarily in the retina but also in brain, gut, and immune cells. - The GABRR3 gene is located at chromosomal locus 3q11.2, distinct from GABRR1 and GABRR2, and its promoter contains binding sites for transcription factors like Sp1, AP-1, NRSF, and C/EBP, suggesting complex transcriptional regulation. - GABRR3 protein exhibits a conserved Cys-loop receptor architecture with an extracellular N-terminal domain for GABA binding and a transmembrane domain forming the ion pore, capable of forming homomeric and heteromeric channels with other rho subunits. - GABRR3 expression is modulated by peripheral immune activation, linking systemic inflammation to central GABAergic signaling, and its gene variants are implicated in neurological conditions such as migraine, restless legs syndrome, and essential tremor. - Pharmacogenomic studies suggest GABRR3 variants may predict interferon-beta treatment response in multiple sclerosis, and selective modulators of GABRR3-containing receptors are being explored as therapeutic targets for various neurological and ocular disorders. --- ## Executive Summary & Key Metadata The gamma-aminobutyric acid (GABA) type A receptor subunit rho 3 (GABRR3) is a member of the rho (ρ) subfamily of GABA receptor subunits, which historically have been classified as forming "GABAC" receptors. These receptors are pentameric ligand-gated chloride channels that mediate fast inhibitory neurotransmission, primarily in the retina, but with documented expression in the brain, gut, and immune cells. GABRR3 is the most recently identified and least characterized of the three rho subunits (GABRR1, GABRR2, GABRR3). Its gene structure, protein topology, and physiological roles are distinct from the more abundant GABRR1 and GABRR2, yet it retains the capacity to form functional homomeric and heteromeric channels. This manual provides a definitive, biophysically detailed reference for GABRR3, integrating genomic, structural, functional, and clinical data. The gene has been implicated in a range of neurological and psychiatric conditions, including migraine, restless legs syndrome (RLS), essential tremor, and potentially schizophrenia and epilepsy. Furthermore, GABRR3 expression is modulated by peripheral immune activation, suggesting a link between systemic inflammation and central GABAergic signaling. Pharmacogenomic studies have also explored GABRR3 variants as predictors of interferon-beta (IFN-β) treatment response in multiple sclerosis (MS). | **Attribute** | **Detail** | | :--- | :--- | | **HGNC Symbol** | GABRR3 | | **UniProt Accession** | A8MPY1 | | **Representative PDB ID** | true (Homology models available; experimental structure pending) | | **Chromosomal Locus** | 3q11.2 (GRCh38/hg38) | | **Primary Molecular Function** | GABA-gated chloride channel subunit; forms pentameric ionotropic receptors | | **Disease & Pathology Associations** | Migraine, Restless Legs Syndrome (RLS), Essential Tremor, Multiple Sclerosis (treatment response), Schizophrenia, Epilepsy (indirect evidence) | --- ## 1. Genomic Locus, Chromosomal Organization & Isoforms ### 1.1 Chromosomal Localization and Gene Structure The GABRR3 gene is located on the long arm of chromosome 3 at cytogenetic band 3q11.2. This locus is distinct from the clustered GABRR1 and GABRR2 genes, which reside on chromosome 6q15. The genomic coordinates for GABRR3 (GRCh38/hg38 assembly) are approximately chr3: 97,850,000–97,900,000 (exact coordinates vary by annotation release). The gene is oriented on the minus strand. The genomic architecture of GABRR3 is characterized by a relatively compact structure, spanning approximately 50 kilobases (kb). It consists of 9 exons and 8 introns, a structure that is highly conserved among the rho subunit family. The coding sequence (CDS) is approximately 1,400 base pairs (bp), encoding a precursor protein of 466 amino acids. The mature protein, after cleavage of the N-terminal signal peptide (approximately 20 amino acids), is about 446 amino acids in length. ### 1.2 Promoter Architecture and Regulatory Elements The promoter region of GABRR3 lacks a canonical TATA box, a feature common to many neuronal genes that require precise spatiotemporal regulation. Instead, the promoter is GC-rich and contains multiple putative binding sites for constitutively expressed and inducible transcription factors. In silico promoter analysis predicts binding sites for: - **Specificity Protein 1 (Sp1):** A ubiquitous transcription factor that regulates housekeeping and tissue-specific genes. Sp1 binding sites are common in TATA-less promoters and are essential for basal transcription. - **Activating Protein 1 (AP-1):** A dimeric transcription factor composed of Jun and Fos family proteins. AP-1 sites mediate responses to stress, cytokines, and growth factors, providing a mechanism for the observed upregulation of GABRR3 during peripheral inflammatory responses [1]. - **Neuron-Restrictive Silencer Factor (NRSF/REST):** A master regulator of neuronal gene expression. NRSF binding sites in the GABRR3 promoter could restrict its expression to specific neuronal populations, explaining its limited distribution compared to GABRR1. - **CCAAT/Enhancer-Binding Protein (C/EBP):** A family of transcription factors involved in cellular differentiation and immune responses. C/EBP sites may link GABRR3 expression to inflammatory signaling cascades. ### 1.3 Enhancer Elements and Chromatin Architecture Chromatin immunoprecipitation sequencing (ChIP-seq) data from the ENCODE project reveal that the GABRR3 locus is embedded within a larger topologically associating domain (TAD) that includes several other genes. Within this TAD, multiple enhancer elements have been identified, particularly in intronic regions and in the intergenic space downstream of the gene. These enhancers are marked by histone modifications such as H3K27ac (acetylation of lysine 27 on histone H3) and H3K4me1 (monomethylation of lysine 4 on histone H3), which are hallmarks of active regulatory elements. The three-dimensional chromatin architecture places these enhancers in close proximity to the GABRR3 promoter in retinal and specific brain tissues, facilitating robust transcriptional activation. The long-range interactions are cell-type specific, suggesting that GABRR3 expression is tightly controlled by developmental and environmental cues. ### 1.4 Alternative Splicing and Isoforms Alternative splicing is a major source of functional diversity for GABA receptor subunits. While GABRR3 does not exhibit the extensive splicing repertoire of GABRR1 or GABRR2, at least two transcript variants have been annotated in public databases (Ensembl, NCBI). - **Transcript Variant 1 (Canonical):** Encodes the full-length 466-amino acid protein (UniProt: A8MPY1-1). This is the predominant and functionally characterized isoform. - **Transcript Variant 2:** Predicted to encode a truncated protein due to the use of an alternative acceptor splice site in intron 6. This variant introduces a premature stop codon, resulting in a protein lacking the majority of the extracellular N-terminal domain and all transmembrane domains. This isoform is likely a candidate for nonsense-mediated mRNA decay (NMD) and may not produce a stable protein. However, if translated, it could act as a dominant-negative regulator by sequestering interacting proteins. The regulation of these splice variants is not fully understood, but RNA-seq data from the Genotype-Tissue Expression (GTEx) project indicate that the canonical isoform is overwhelmingly dominant in all tissues where GABRR3 is expressed. --- ## 2. 3D Protein Domain Architecture & Structural Biology ### 2.1 Topological Overview The GABRR3 protein, like all Cys-loop receptor subunits, shares a conserved three-dimensional architecture. The full-length protein is composed of three distinct domains: 1. **Extracellular N-Terminal Domain (ECD):** Residues ~1-240 (after signal peptide cleavage). This domain contains the signature Cys-loop motif and the primary agonist (GABA) binding site. 2. **Transmembrane Domain (TMD):** Residues ~241-430. This domain is composed of four α-helical membrane-spanning segments (TM1-TM4). TM2 lines the ion channel pore. 3. **Intracellular Loop and C-Terminus:** Residues ~431-466. This domain is highly variable among subunits and contains sites for phosphorylation and protein-protein interactions. ### 2.2 Extracellular Domain (ECD) and Ligand-Binding Pocket The ECD is the most structurally complex region. It adopts a "immunoglobulin-like" β-sandwich fold, consisting of 10 β-strands arranged in a Greek-key topology. The hallmark of this family is the **Cys-loop**, a disulfide bond formed between two highly conserved cysteine residues (Cys-X-X-X-X-Cys) located in the β6-β7 loop. This disulfide bridge is critical for the structural stability of the ECD and for the proper folding and trafficking of the receptor to the cell surface. The agonist binding site is located at the interface between two adjacent subunits. In a homomeric GABRR3 receptor, the principal face of one subunit (the (+) face) contributes three loops (A, B, and C) to the binding pocket, while the complementary face of the adjacent subunit (the (−) face) contributes three β-strands (loops D, E, and F). Key residues involved in GABA binding in rho subunits include conserved aromatic residues (e.g., Tyr, Phe, Trp) that form a hydrophobic "aromatic box" that coordinates the amine and carboxyl groups of GABA. In GABRR3, the specific residues are predicted to be homologous to those in GABRR1 (e.g., Tyr102, Phe138, Tyr198, etc.), but with subtle differences that may account for distinct pharmacological profiles. ### 2.3 Transmembrane Domain (TMD) and Ion Channel Pore The TMD is composed of four α-helical segments (TM1-TM4). TM2 is the critical pore-lining helix. In the pentameric assembly, five TM2 helices (one from each subunit) come together to form the central ion-conducting pore. The pore is lined with hydrophilic and charged residues that confer anion selectivity (primarily Cl⁻). The ion channel has three functional states: **resting (closed)**, **open (conducting)**, and **desensitized (closed but agonist-bound)**. The transition between these states is mediated by conformational changes in the ECD that are transmitted to the TMD via a conserved "coupling" region. The TM2-TM3 loop is a critical transduction element. Mutations in this loop can uncouple agonist binding from channel opening, leading to a loss of function. The intracellular loop between TM3 and TM4 is the most divergent region among subunits. For GABRR3, this loop contains several consensus sites for protein kinase C (PKC) and protein kinase A (PKA) phosphorylation. These post-translational modifications can modulate channel kinetics, receptor desensitization, and cell surface expression. ### 2.4 Quaternary Structure and Stoichiometry GABRR3 subunits can assemble into functional pentameric receptors. While GABRR1 and GABRR2 readily form homomeric receptors, GABRR3's ability to form functional homomers is debated. Evidence suggests that GABRR3 can form homomeric channels, but with lower efficiency than GABRR1. More importantly, GABRR3 can co-assemble with GABRR1 and GABRR2 to form heteromeric receptors with distinct stoichiometries (e.g., 2:3 or 3:2 ratios). These heteromeric receptors exhibit different pharmacological properties, such as altered sensitivity to GABA and to the competitive antagonist bicuculline. ### 2.5 Interactive 3D Visualizer To explore the predicted three-dimensional structure of the GABRR3 protein, including its domain architecture and ligand-binding pockets, use the interactive visualizer below. This tool loads a high-quality homology model based on the cryo-EM structure of the related GABRR1 subunit. [**Interactive 3D Protein Visualizer: Load GABRR3 (PDB: true)**](/tools/protein-structure-viewer?source=alphafold&accession=A8MPY1) --- ## 3. Cellular Signaling Pathways & Molecular Function ### 3.1 The GABAergic Signaling Cascade GABRR3 is an integral component of the inhibitory GABAergic signaling system. The primary function of the assembled GABRR3-containing receptor is to mediate fast synaptic and extrasynaptic inhibition by conducting chloride ions (Cl⁻) into the cell. The signaling cascade is as follows: 1. **Presynaptic Release:** An action potential arrives at the presynaptic terminal, triggering the release of GABA from synaptic vesicles into the synaptic cleft. 2. **Receptor Activation:** GABA diffuses across the cleft and binds to the orthosteric site on the GABRR3-containing receptor. 3. **Channel Opening:** Agonist binding induces a conformational change that opens the channel pore, allowing Cl⁻ to flow down its electrochemical gradient. 4. **Membrane Hyperpolarization:** In most mature neurons, the intracellular Cl⁻ concentration is low, so the influx of Cl⁻ makes the membrane potential more negative (hyperpolarization), moving it away from the threshold for action potential generation. This reduces neuronal excitability. 5. **Termination of Signal:** The signal is terminated by the dissociation of GABA and the closure of the channel (deactivation), followed by the reuptake of GABA by transporters (GATs) on the presynaptic terminal and surrounding glial cells. ### 3.2 Functional Roles in the Retina and Brain - **Retina:** GABRR3 is highly expressed in the retina, particularly in bipolar cells and ganglion cells. It contributes to the high-sensitivity, sustained inhibitory responses that are characteristic of GABAC receptors. These receptors are involved in processing visual information, including contrast detection and motion sensing. - **Brain:** GABRR3 expression in the brain is more restricted but has been detected in the hippocampus, cortex, and cerebellum. It is thought to mediate tonic inhibition, a form of persistent inhibition that regulates overall neuronal excitability and network synchrony. This role is particularly relevant to conditions like epilepsy and schizophrenia, where excitation-inhibition balance is disrupted [2, 3]. - **Other Tissues:** GABRR3 mRNA has been detected in the gastrointestinal tract, pancreas, and immune cells (e.g., T lymphocytes). In immune cells, GABA signaling can modulate cytokine release and inflammatory responses, providing a direct link between the nervous and immune systems. ### 3.3 Protein-Protein Interaction Networks The function of GABRR3 is modulated by a network of interacting proteins. Key interactions include: - **Gephyrin:** A scaffolding protein that anchors inhibitory receptors to the cytoskeleton at synapses. While gephyrin is primarily associated with GABAA receptors, it may also interact with rho subunits, stabilizing them at synaptic and extrasynaptic sites. - **GABAA Receptor Associated Protein (GABARAP):** A protein involved in receptor trafficking and clustering. GABARAP binds to the intracellular loop of GABA receptor subunits and facilitates their transport to the cell surface. - **Protein Kinase C (PKC) and Protein Kinase A (PKA):** These kinases phosphorylate the intracellular loop of GABRR3, modulating channel function. PKC activation typically reduces receptor function, while PKA can either enhance or inhibit depending on the specific phosphorylation site. - **RACK1 (Receptor for Activated C Kinase 1):** A scaffolding protein that anchors activated PKC near its substrates. RACK1 may facilitate the PKC-mediated phosphorylation of GABRR3. ### 3.4 Regulatory Feedback Loops GABRR3 expression is subject to feedback regulation. Chronic exposure to GABA or GABAergic drugs can lead to receptor desensitization and downregulation. Conversely, prolonged blockade of GABAergic transmission can lead to receptor upregulation (homeostatic plasticity). These processes involve changes in gene transcription, mRNA stability, and protein degradation. A notable regulatory pathway involves the **peripheral acute phase response (APR)** . A study by Michalovicz and Konat (2013) demonstrated that a peripherally restricted APR, induced by a viral mimic (polyinosinic-polycytidylic acid, PIC), alters hippocampal gene expression, including genes related to GABAergic signaling [1]. This suggests that systemic inflammation can influence central GABA receptor expression, potentially contributing to the neuropsychiatric symptoms associated with chronic inflammatory diseases. ```mermaid flowchart TD A["Peripheral Inflammation / Viral Mimic (PIC)"] --> B["Acute Phase Response in Liver"] B --> C["Release of Cytokines (IL-6, TNF-alpha)"] C --> D["Blood-Brain Barrier Transport / Signaling"] D --> E["Altered Transcription Factor Activity in Hippocampal Neurons"] E --> F["Upregulation / Downregulation of GABRR3 Gene Expression"] F --> G["Changes in GABRR3 Receptor Density on Cell Surface"] G --> H["Altered Inhibitory Neurotransmission"] H --> I["Increased Susceptibility to Excitotoxic Insult / Neuronal Hyperexcitability"] ``` --- ## 4. Pathogenic Hotspot Mutations & Clinical Differentials ### 4.1 Common Polymorphisms and Disease Associations GABRR3 is not a highly polymorphic gene, but several single nucleotide polymorphisms (SNPs) have been investigated for associations with neurological and psychiatric disorders. #### 4.1.1 Migraine A case-control study by García-Martín et al. (2017) analyzed the association between polymorphisms in GABA receptor rho genes (GABRR1, GABRR2, GABRR3) and the risk for migraine [4]. The study genotyped several SNPs in a Spanish cohort. While the primary findings implicated GABRR1 and GABRR2, the analysis of GABRR3 SNPs suggested a potential, albeit weaker, modifying effect. The study concluded that variations in rho subunit genes may contribute to migraine susceptibility, likely by altering the inhibitory tone in pain-processing pathways. #### 4.1.2 Restless Legs Syndrome (RLS) RLS is a neurological disorder characterized by an irresistible urge to move the legs, often accompanied by unpleasant sensations. Several candidate gene studies have explored the role of GABAergic genes in RLS. - **Jiménez-Jiménez et al. (2018)** investigated the association between GABRR gene polymorphisms and RLS risk in a Spanish population [5]. They found that certain SNPs in GABRR1 and GABRR3 were associated with RLS susceptibility, although the effect sizes were modest. - **Chen et al. (2019)** conducted a genetic association study of RLS in a Chinese population, examining several candidate genes, including GABA receptor subunits [6]. The study found no significant association for GABRR3 in the Asian cohort, highlighting potential ethnic differences in genetic risk factors. - **Schormair et al. (2022)** performed a reassessment of candidate gene studies for RLS in a large GWAS dataset of European ancestry [7]. This study found that most previously reported candidate gene associations, including those for GABRR3, were not replicated in the larger dataset. This suggests that the initial findings may have been false positives or that the effect sizes are too small to be detected in GWAS. - **Tan et al. (2024)** conducted a systematic review of genetic association studies in RLS, highlighting the common gene variants and ethnic differences [8]. The review concluded that the genetic architecture of RLS is complex and that many candidate gene associations, including those for GABRR3, remain unconfirmed. #### 4.1.3 Essential Tremor Essential tremor (ET) is one of the most common movement disorders. García-Martín et al. (2011) investigated the association between GABRR polymorphisms and the risk for ET [9]. The study found a significant association between a specific haplotype in the GABRR genes and ET risk, suggesting that GABAergic dysfunction may contribute to the pathogenesis of ET. #### 4.1.4 Schizophrenia and Epilepsy While not directly studied for GABRR3, the related gene GABRR1 has been associated with susceptibility to bipolar schizoaffective disorder [3]. Furthermore, copy number variations (CNVs) in genes involved in neuronal signaling, such as CNTNAP2, have been associated with schizophrenia and epilepsy [2]. These findings support the broader hypothesis that disruptions in inhibitory signaling pathways are central to the pathophysiology of these disorders. Given its role in tonic inhibition, GABRR3 is a plausible candidate gene for these conditions, warranting further investigation. ### 4.2 Rare Variants and Longevity A study by Han et al. (2013) used target capture and next-generation sequencing to discover novel non-synonymous SNP variants in 988 candidate genes from 6 centenarians [10]. The goal was to identify rare genetic variants that may contribute to exceptional longevity. The study identified several novel variants, including some in genes related to neurotransmission. While GABRR3 was not specifically highlighted, this study demonstrates the utility of deep sequencing for identifying rare functional variants in candidate genes. ### 4.3 Pathogenic Variants in ClinVar As of the latest data update, ClinVar contains few entries for GABRR3. Most variants are classified as "Benign" or "Likely Benign" or are of "Uncertain Significance." No definitive pathogenic variants causing a Mendelian disorder have been identified. This suggests that GABRR3 is not a major disease gene for monogenic conditions, but its common variants may act as risk modifiers for complex traits. --- ## 5. Host-Pathogen & Viral Interactions ### 5.1 Modulation by Viral Mimics and Inflammation The interaction between GABRR3 and pathogens is indirect but significant. The study by Michalovicz and Konat (2013) provides a clear link between a viral mimic (PIC) and altered GABAergic gene expression in the brain [1]. The proposed mechanism involves the following steps: 1. **Peripheral Immune Activation:** Intraperitoneal injection of PIC, a synthetic double-stranded RNA analog that mimics a viral infection, triggers a robust APR in the periphery. 2. **Cytokine Release:** The APR leads to the release of pro-inflammatory cytokines, such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), into the bloodstream. 3. **Central Signaling:** These cytokines can signal to the brain via several pathways, including active transport across the blood-brain barrier (BBB), signaling through circumventricular organs (which lack a tight BBB), and activation of endothelial cells lining the brain vasculature. 4. **Transcriptional Changes:** The central cytokine signaling activates transcription factors (e.g., NF-κB, STAT3) in glial cells and neurons, leading to changes in the expression of a wide array of genes, including GABRR3. 5. **Altered Neuronal Excitability:** The change in GABRR3 expression alters the balance of inhibitory neurotransmission, rendering the brain hypersusceptible to subsequent excitotoxic insults, such as those induced by kainic acid. This finding has implications for understanding the neuropsychiatric sequelae of viral infections and chronic inflammatory conditions. It suggests that GABRR3 is a molecular link between the immune system and the central nervous system. ### 5.2 Direct Viral Interactions There is no direct evidence that viral proteins bind to or degrade the GABRR3 protein. However, several neurotropic viruses, such as herpes simplex virus (HSV) and rabies virus, are known to dysregulate GABAergic signaling to enhance their replication and spread. It is plausible that these viruses modulate GABRR3 expression indirectly through the inflammatory pathways described above, but this remains an area of active investigation. --- ## 6. Pharmacogenomics, Drug Targets & Small-Molecule Inhibitors ### 6.1 GABRR3 as a Drug Target The rho subunit-containing receptors (GABAC) are attractive drug targets due to their restricted expression pattern and distinct pharmacology compared to GABAA receptors. Targeting GABRR3 specifically could provide therapeutic benefits with fewer side effects than non-selective GABAergic drugs. - **Eye Disorders:** Since GABRR3 is highly expressed in the retina, selective modulators could be used to treat conditions like glaucoma, myopia, and retinal ischemia. - **Neurological Disorders:** Modulating tonic inhibition in the brain could be beneficial for epilepsy, schizophrenia, and chronic pain. - **Substance Abuse:** GABAergic drugs are used to manage alcohol withdrawal and dependence. GABRR3 modulators could potentially be used to mitigate the effects of ethanol on motor function [11]. ### 6.2 Known Modulators - **Agonists:** GABA is the endogenous agonist. Other agonists include *trans*-4-aminocrotonic acid (TACA) and cis-4-aminocrotonic acid (CACA). These compounds are more selective for rho subunits than for GABAA receptors. - **Antagonists:** The plant alkaloid bicuculline is a classic GABAA antagonist but is ineffective at rho-containing receptors. The competitive antagonist (1,2,5,6-tetrahydropyridin-4-yl)methylphosphinic acid (TPMPA) is a selective antagonist for rho subunits. - **Allosteric Modulators:** Several compounds, including neurosteroids and barbiturates, can modulate rho receptor function, but their selectivity for GABRR3 over other rho subunits is not well established. - **Ethanol:** GABAA receptors are sensitive to ethanol at concentrations achieved during social drinking. A study by García-Martín et al. (2018) investigated the association between missense GABA receptor polymorphisms and reaction time, motor time, and ethanol effects in vivo [11]. The study found that specific polymorphisms in GABA receptor genes, including potentially GABRR3, were associated with differential sensitivity to ethanol's effects on motor performance. ### 6.3 Pharmacogenomics in Multiple Sclerosis A pharmacogenomic study by Bustamante et al. (2015) investigated the association between polymorphisms in various genes and the response to IFN-β treatment in patients with multiple sclerosis (MS) [12]. The study included genes encoding neurotransmitter receptors, including GABA receptor subunits. The rationale was that the therapeutic response to IFN-β might be influenced by the patient's baseline neuronal excitability and immune regulation. The study identified several SNPs that were associated with treatment response, although the specific role of GABRR3 in this context requires further validation. ### 6.4 Future Therapeutic Strategies - **Small Molecules:** High-throughput screening could identify novel small molecules that selectively modulate GABRR3-containing receptors. - **Monoclonal Antibodies:** Antibodies targeting the extracellular domain of GABRR3 could be used to modulate receptor function or to deliver cytotoxic payloads to GABRR3-expressing cells (e.g., in cancer). - **Gene Therapy:** For conditions caused by GABRR3 loss-of-function, gene therapy vectors (e.g., AAV) could deliver a functional copy of the gene. Conversely, for conditions caused by gain-of-function, RNA interference (RNAi) or antisense oligonucleotides (ASOs) could be used to knock down GABRR3 expression. - **CRISPR/Cas9:** Gene editing could be used to correct pathogenic mutations in GABRR3, although this approach is still in its infancy for neurological disorders. --- ## 7. Bioinformatic Resources & Database Accessions The following table provides key database accessions for GABRR3. | **Database** | **Accession ID** | **Description** | | :--- | :--- | :--- | | **HGNC** | 20969 | Official gene symbol and name | | **NCBI Gene** | 200959 | Gene-specific information, genomic context, and links to other databases | | **Ensembl** | ENSG00000184345 | Comprehensive genome annotation, including transcripts and variation | | **UniProt** | A8MPY1 | Protein sequence, function, and post-translational modifications | | **RCSB PDB** | N/A (Homology models) | Experimental 3D structures (none available for GABRR3; models based on GABRR1) | | **OMIM** | 610190 | Mendelian inheritance and disease associations | | **ClinVar** | Gene: GABRR3 | Human genetic variants and their clinical significance | | **GTEx** | GABRR3 | Tissue-specific gene expression data | | **STRING** | GABRR3 | Protein-protein interaction networks | | **BioGRID** | GABRR3 | Physical and genetic interactions | | **Gene Ontology (GO)** | GO:0004890 (GABA-A receptor activity), GO:0005230 (extracellular ligand-gated ion channel activity), GO:0006811 (ion transport), GO:0007268 (chemical synaptic transmission) | Functional annotations | --- ## Related Clinical & Scientific Guides * [SYNGR1 Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/neuroscience-genetics/syngr1-gene-structure-function-pathway) * [RGS12 Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/neuroscience-genetics/rgs12-gene-structure-function-pathway) * [CHRNB1 Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/neuroscience-genetics/chrnb1-gene-structure-function-pathway) ## References [1] Michalovicz, L., & Konat, G. 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