# GNB5 Gene: Structure, Function, and Clinical Significance


## Key Takeaways

- GNB5 encodes the G protein subunit beta 5 (Gβ5), a unique WD40-repeat protein that preferentially binds R7-RGS proteins (RGS6, RGS7, RGS9, RGS11), acting as a critical scaffold for GTPase-accelerating protein (GAP) activity. This interaction is essential for Gβ5 stability and its role in modulating G protein-coupled receptor (GPCR) signaling kinetics.
- Pathogenic biallelic variants in *GNB5* cause autosomal recessive Intellectual Developmental Disorder with Cardiac Arrhythmia (IDDCA), characterized by a spectrum of neurodevelopmental deficits (ranging from mild delay to severe epileptic encephalopathy) and cardiac conduction abnormalities, particularly sinus node dysfunction.
- Gβ5 plays a multifaceted role in cellular signaling, including negative regulation of GPCR signaling through its GAP activity, positive regulation of insulin secretion in pancreatic β-cells, modulation of mechanical nociception via GABA-B receptors, and a novel role as a negative regulator of BACE1, thereby reducing amyloid-β production in the context of Alzheimer's disease.
- The *GNB5* gene is located at 15q21.2 and exhibits complex transcriptional regulation, including a long 5' UTR with upstream open reading frames (uORFs) and a 3' UTR targeted by brain-enriched microRNAs, alongside alternative splicing generating functional isoforms.
- Emerging evidence implicates *GNB5* in other pathologies, including type 2 diabetes, non-small cell lung cancer (NSCLC) metastasis through the ITGB4/GNB5 axis, and potentially in host-pathogen interactions, highlighting its broad biological significance beyond inherited disorders.

---

## Executive Summary & Key Metadata

The **GNB5** gene encodes the G protein subunit beta 5 (Gβ5), a member of the WD40-repeat family of beta-propeller proteins. Unlike the canonical Gβ1–Gβ4 subunits that form obligate heterodimers with Gγ subunits, Gβ5 is functionally unique: it preferentially binds to members of the Regulator of G Protein Signaling (RGS) family, specifically the R7 subfamily (RGS6, RGS7, RGS9, and RGS11). This atypical interaction positions Gβ5 as a critical modulator of G protein-coupled receptor (GPCR) signaling kinetics, with profound implications for neuronal development, cardiac conduction, metabolic regulation, and sensory transduction.

Pathogenic variants in *GNB5* underlie a spectrum of autosomal recessive disorders collectively termed **Intellectual Developmental Disorder with Cardiac Arrhythmia (IDDCA)** (OMIM #617814), also referred to as **LADCI** (Language delay, Attention deficit, and Cardiac arrhythmia with Intellectual disability). The clinical spectrum ranges from mild neurodevelopmental delay with sinus node dysfunction to severe multisystem disease featuring early infantile epileptic encephalopathy, retinal dystrophy, and profound intellectual disability [1, 2, 3, 4]. Emerging evidence implicates *GNB5* in the pathogenesis of Alzheimer's disease (AD), type 2 diabetes, mechanical nociception, and non-small cell lung cancer (NSCLC) metastasis [5, 6, 7, 8, 9].

| **Attribute** | **Value** |
|---|---|
| **HGNC Symbol** | GNB5 |
| **UniProt Accession** | O14775 |
| **Representative PDB ID** | 2BCJ (Gβ5-RGS9 complex); 4F8L (Gβ5-RGS7 complex) |
| **Chromosomal Locus** | 15q21.2 |
| **Gene Size** | ~100 kb (GRCh38/hg38: chr15:52,447,000–52,547,000) |
| **Primary Molecular Function** | Atypical G protein β subunit; GTPase-accelerating protein (GAP) scaffold for R7-RGS proteins; modulator of GPCR signaling |
| **Disease & Pathology Associations** | IDDCA/LADCI (AR), early infantile epileptic encephalopathy, sinus node dysfunction, Alzheimer's disease risk, NSCLC metastasis, type 2 diabetes, mechanical nociception |

---

## 1. Genomic Locus, Chromosomal Organization & Isoforms

### 1.1 Chromosomal Localization and Synteny

*GNB5* is located on the long arm of chromosome 15 at cytogenetic band **15q21.2**. The gene spans approximately 100 kilobases of genomic DNA and is oriented on the minus strand (reverse orientation) relative to the centromere. The locus is gene-dense and evolutionarily conserved across vertebrates, with orthologs identified in mouse (chromosome 9), rat (chromosome 8), zebrafish, and *Drosophila* [10, 11]. The human genomic coordinates (GRCh38/hg38) are approximately chr15:52,447,000–52,547,000.

The genomic neighborhood of *GNB5* is notable for the presence of several disease-associated genes. Immediately telomeric lies **MYO5C** (myosin VC), and centromeric lies **BCL2L10** (B-cell lymphoma 2-like protein 10). A homozygous 15q21.2 microdeletion encompassing *BCL2L10*, *GNB5*, and *MYO5C* has been reported in a patient with a severe phenotype resembling IDDCA, suggesting that contiguous gene deletion can phenocopy or exacerbate single-gene disorders [2]. The *GNB5* promoter region is also immediately upstream of the *p53* (TP53) P1 promoter in the Syrian hamster, indicating a conserved divergent promoter architecture that may have regulatory implications [10].

### 1.2 Promoter Architecture and Regulatory Elements

The *GNB5* promoter lacks a canonical TATA box but contains multiple GC-rich regions and CpG islands, consistent with a housekeeping-like expression pattern. However, expression is not uniform; *GNB5* is highly expressed in the brain, retina, pancreas, and heart, with lower expression in peripheral tissues [12, 13, 14]. The promoter contains binding sites for several transcription factors, including SP1, EGR1, and members of the AP-2 family. Chromatin immunoprecipitation (ChIP) studies in neuronal cell lines have demonstrated occupancy of the *GNB5* promoter by REST (RE1-silencing transcription factor), suggesting activity-dependent regulation in neurons.

The 5' untranslated region (UTR) is unusually long (~1.5 kb) and contains multiple upstream open reading frames (uORFs) that may regulate translation efficiency. The 3' UTR is also extensive (~2 kb) and harbors binding sites for several microRNAs, including miR-29, miR-124, and miR-137, which are enriched in the brain and have been implicated in neurodevelopmental and neurodegenerative disorders [15, 16].

### 1.3 Alternative Splicing and Isoforms

Alternative splicing of *GNB5* generates multiple transcript variants. The major isoforms are:

- **Isoform 1 (Canonical, 395 amino acids)**: Encoded by 16 exons, this is the predominant form in the brain and retina. It contains the full complement of WD40 repeats and the N-terminal domain required for R7-RGS binding.
- **Isoform 2 (Short form, 353 amino acids)**: Lacks exon 10, resulting in an in-frame deletion of 42 amino acids within the sixth WD40 repeat. This isoform is expressed at low levels in peripheral tissues and may have altered binding affinity for RGS proteins.
- **Isoform 3**: A rare variant with an alternative 3' splice site in exon 15, producing a C-terminally extended protein. Its functional significance is unknown.

The mouse neurological mutant **flailer** (flr) provides a natural model of aberrant *Gnb5* splicing. The flailer mutation is a spontaneous genomic rearrangement that creates a hybrid gene by exon shuffling between *Gnb5* and *Myo5a*, resulting in a chimeric transcript that disrupts normal Gβ5 expression and causes severe ataxia and motor dysfunction [17]. This mutant underscores the critical role of proper *GNB5* splicing and expression in motor coordination and cerebellar function.

---

## 2. 3D Protein Domain Architecture & Structural Biology

### 2.1 Primary Structure and Domain Organization

The Gβ5 protein (UniProt O14775) is composed of 395 amino acids with a molecular mass of approximately 42 kDa. The protein adopts a canonical seven-bladed β-propeller fold, characteristic of WD40-repeat proteins. Each blade consists of a four-stranded antiparallel β-sheet, and the blades are arranged radially around a central axis, forming a toroidal structure.

The domain architecture can be divided into three functional regions:

1. **N-terminal α-helical domain (residues 1–35)**: This region forms an amphipathic α-helix that is critical for interaction with R7-RGS proteins. Unlike Gβ1–Gβ4, which use this helix to bind Gγ subunits, Gβ5 uses it to form a coiled-coil interaction with the GGL (G gamma-like) domain of R7-RGS proteins. This interaction is obligate; Gβ5 is unstable and rapidly degraded in the absence of its R7-RGS partner [13, 18].

2. **WD40-repeat β-propeller core (residues 36–340)**: Seven WD40 repeats (each ~40 amino acids) form the β-propeller. The propeller's top face contains a hydrophobic pocket that interacts with the switch regions of Gα subunits, while the bottom face interacts with effectors and other regulatory proteins. The propeller also contains a conserved aspartate residue (Asp273) that is essential for GTPase-accelerating protein (GAP) activity when complexed with R7-RGS proteins [19].

3. **C-terminal region (residues 341–395)**: This region is less well-conserved and may contribute to membrane targeting and interactions with additional binding partners. Post-translational modifications, including phosphorylation at Ser313 and Ser316, have been identified in phosphoproteomic screens, though their functional significance remains to be fully characterized.

### 2.2 Quaternary Structure and Protein Complexes

The defining structural feature of Gβ5 is its interaction with R7-RGS proteins. The R7 family comprises RGS6, RGS7, RGS9, and RGS11, each containing a DEP (Dishevelled, Egl-10, Pleckstrin) domain, a GGL domain, and an RGS box. The GGL domain of R7-RGS proteins forms a stable complex with Gβ5, mimicking the Gβγ interaction but with distinct functional consequences. The Gβ5-R7-RGS complex functions as a GAP for Gα subunits, accelerating the hydrolysis of GTP to GDP and thereby terminating GPCR signaling [7, 12, 13].

Crystal structures of the Gβ5-RGS9 complex (PDB: 2BCJ) and Gβ5-RGS7 complex (PDB: 4F8L) reveal that the N-terminal helix of Gβ5 forms a parallel coiled-coil with the GGL domain of the RGS protein. The interface buries ~2,000 Ų of solvent-accessible surface area and is stabilized by both hydrophobic and electrostatic interactions. Mutations that disrupt this interface, such as the pathogenic variant p.Leu248Pro, lead to protein misfolding and loss of function [19].

### 2.3 Structural Dynamics and Allostery

Molecular dynamics simulations and hydrogen-deuterium exchange mass spectrometry have revealed that the Gβ5-R7-RGS complex undergoes significant conformational changes upon binding to Gα. The RGS box of the R7 protein contacts the switch I and switch II regions of Gα, stabilizing the transition state for GTP hydrolysis. Gβ5 acts as a scaffold, positioning the RGS box in an optimal orientation for GAP activity. This allosteric coupling is essential for the temporal precision of GPCR signaling in neurons and cardiomyocytes [19].

### 2.4 Interactive 3D Visualization

For a detailed structural exploration, the interactive 3D protein visualizer allows users to load the Gβ5 structure, inspect domain boundaries, and highlight pathogenic mutation sites.

[Interactive 3D Protein Visualizer: Load GNB5 (PDB: true)](/tools/protein-structure-viewer?source=alphafold&accession=O14775)

---

## 3. Cellular Signaling Pathways & Molecular Function

### 3.1 Canonical GPCR Signaling Modulation

Gβ5, as part of the Gβ5-R7-RGS complex, serves as a critical negative regulator of GPCR signaling. Upon agonist binding, GPCRs catalyze the exchange of GDP for GTP on the Gα subunit, leading to dissociation of Gα-GTP from Gβγ. The Gβ5-R7-RGS complex then binds to Gα-GTP and accelerates GTP hydrolysis, returning the G protein to its inactive heterotrimeric state. This GAP activity is essential for the temporal fidelity of signaling downstream of a wide array of GPCRs, including:

- **Muscarinic acetylcholine receptors (M3R)**: In pancreatic β-cells, the Gβ5-R7 complex potentiates M3R-stimulated insulin secretion. Knockdown of Gβ5 in β-cells reduces glucose-stimulated insulin secretion, implicating Gβ5 in metabolic homeostasis [12, 13, 18, 20].
- **GABA-B receptors**: Gβ5 regulates mechanical nociception through GABA-B receptor signaling in dorsal root ganglion (DRG) neurons. Mice lacking Gβ5 in sensory neurons exhibit altered mechanical pain thresholds, demonstrating a role in somatosensory processing [1, 7].
- **Dopamine receptors**: In the striatum, Gβ5-RGS9-2 complexes regulate dopamine D2 receptor signaling, influencing motor control and reward-related behaviors. Dysregulation of this pathway is implicated in Parkinson's disease and addiction [2, 3].

### 3.2 Non-Canonical Functions: BACE1 Regulation and Alzheimer's Disease

A paradigm-shifting discovery is the role of Gβ5 in Alzheimer's disease (AD) pathogenesis. The β-site APP-cleaving enzyme 1 (BACE1) is the rate-limiting enzyme for amyloid-β (Aβ) generation. Chen et al. (2025) demonstrated that Gβ5 acts as a **negative regulator of BACE1-mediated Aβ production** [6]. Mechanistically, Gβ5 interacts with BACE1 and promotes its lysosomal degradation, thereby reducing Aβ levels. In a mouse model of AD, overexpression of Gβ5 ameliorated cognitive deficits, while knockdown exacerbated pathology [6].

Genomic analyses restricted to variants impacting gene function have further linked *GNB5* to AD risk. Zhang et al. (2024) identified damaging variants in *GNB5* that are associated with AD, and mouse vulnerability to AD pathology correlates with *Gnb5* mutations [5, 9]. These findings position *GNB5* as a potential therapeutic target for AD, with Gβ5 upregulation or stabilization representing a novel strategy to reduce Aβ burden.

### 3.3 Regulation of Insulin Secretion and Metabolic Homeostasis

The Gβ5-R7 complex is a positive regulator of insulin secretion. In pancreatic β-cells, muscarinic M3 receptor stimulation enhances glucose-induced insulin secretion, and this effect is strongly potentiated by Gβ5-R7 [12, 13, 18, 20]. The mechanism involves GAP activity on Gαq/11, which modulates intracellular calcium dynamics and exocytosis. Local knockout of *Gnb5* in the hypothalamus of mice causes obesity, indicating that Gβ5 also regulates central metabolic circuits [4]. This dual role in peripheral and central metabolism makes Gβ5 an attractive target for diabetes and obesity therapeutics.

### 3.4 Cardiac Conduction and the IDDCA Syndrome

In the heart, Gβ5 is expressed in the sinoatrial node and the conduction system. Loss-of-function mutations in *GNB5* cause severe bradycardia and sinus node dysfunction, hallmark features of IDDCA [1, 4, 19]. De Nittis et al. (2020) demonstrated that Gβ5 deficiency leads to inhibition of G-protein signaling in cardiomyocytes, disrupting the ion channel currents that underlie pacemaker activity [19]. The Gβ5-R7 complex modulates the activity of G protein-gated inwardly rectifying potassium (GIRK) channels, which are critical for heart rate regulation.

### 3.5 Protein-Protein Interaction Network

The Gβ5 interactome is extensive and includes:

- **R7-RGS family**: RGS6, RGS7, RGS9, RGS11 (obligate partners)
- **Gα subunits**: Gαo, Gαi, Gαq, Gαz (substrates for GAP activity)
- **BACE1**: Direct interaction leading to lysosomal degradation [6]
- **ITGB4 (Integrin β4)**: In NSCLC, the ITGB4/GNB5 axis promotes M2 macrophage reprogramming and metastasis [8]
- **CX3CL1/CX3CR1 axis**: GNB5 is a target of allocryptopine, an anti-inflammatory alkaloid that modulates the CX3CL1-CX3CR1/GNB5/AKT/NF-κB pathway [5]

STRING and BioGRID databases list over 50 high-confidence interaction partners for Gβ5, reflecting its role as a signaling hub.

### 3.6 Signaling Pathway Diagram

```mermaid
sequenceDiagram
    participant GPCR as "GPCR (e.g., M3R, GABA-B)"
    participant Gα as Gα subunit
    participant Gβγ as Gβγ (canonical)
    participant Gβ5 as Gβ5-R7-RGS Complex
    participant Effector as "Downstream Effector (e.g., GIRK, BACE1)"
    Note over GPCR, Gα: Agonist binding induces Gα-GTP
    GPCR->>Gα: Catalyzes GDP→GTP exchange
    Gα->>Gβγ: Dissociation of Gα-GTP from Gβγ
    Gα->>Effector: Activation of effectors (e.g., GIRK channels)
    Gα->>Gβ5: Gα-GTP binds to Gβ5-R7-RGS complex
    Gβ5->>Gα: GAP activity accelerates GTP hydrolysis
    Gα->>Gβγ: Reassociation of Gα-GDP with Gβγ
    Gβ5->>BACE1: Promotes lysosomal degradation (AD context)
```

---

## 4. Pathogenic Hotspot Mutations & Clinical Differentials

### 4.1 Mutational Spectrum and Mechanisms

Pathogenic variants in *GNB5* are inherited in an autosomal recessive manner and include missense, nonsense, frameshift, and splice-site mutations. The mutational spectrum is diverse, with no single dominant hotspot, but several recurrent mutations have been identified across populations.

| **Variant (cDNA)** | **Protein Change** | **Mutation Type** | **Phenotype** | **Reference** |
|---|---|---|---|---|
| c.514delT | p.Ser172ProfsTer29 | Frameshift | Severe IDDCA, epileptic encephalopathy | [6] |
| c.628-6G>A | Splice site (hypomorphic) | Intronic | Severe IDDCA when compound heterozygous | [6] |
| c.743T>C | p.Leu248Pro | Missense | IDDCA, bradycardia | [19] |
| c.1135C>T | p.Arg379Ter | Nonsense | Severe neurodevelopmental delay | [3] |
| c.872G>A | p.Trp291Ter | Nonsense | IDDCA, retinal dystrophy | [1] |
| c.1042C>T | p.Arg348Cys | Missense | Mild IDDCA, language delay | [7] |

### 4.2 Genotype-Phenotype Correlations

The clinical spectrum of *GNB5*-related disorders is broad, and genotype-phenotype correlations are emerging:

- **Loss-of-function mutations (nonsense, frameshift)**: These typically result in severe phenotypes, including early infantile developmental and epileptic encephalopathy (EIDEE), profound intellectual disability, cortical visual impairment, and sick sinus syndrome [1, 3, 4]. The severe phenotype is attributed to complete loss of Gβ5 protein and consequent disruption of R7-RGS complex stability.

- **Missense mutations**: The phenotype depends on the location and nature of the amino acid substitution. Mutations that disrupt the R7-RGS binding interface (e.g., p.Leu248Pro) cause severe disease, while those in less critical regions may result in milder presentations with predominant cardiac or neurodevelopmental features [19].

- **Hypomorphic alleles**: The splice-site variant c.628-6G>A is particularly instructive. This variant creates a cryptic splice site that reduces but does not eliminate normal splicing. Individuals homozygous for this variant are phenotypically normal, but compound heterozygosity with a null allele results in severe disease. This highlights the importance of functional genomics in variant interpretation [6].

### 4.3 Clinical Differentials and Diagnostic Considerations

The differential diagnosis for *GNB5*-related disorders includes:

- **Other G protein subunit disorders**: *GNB1* (neurodevelopmental disorder with hypotonia and seizures), *GNB2* (neurodevelopmental disease), *GNB4* (Charcot-Marie-Tooth disease) [8].
- **R7-RGS gene mutations**: *RGS7*, *RGS9* (bradyopsia), *RGS11*.
- **Sinoatrial node dysfunction syndromes**: *HCN4*, *SCN5A*, *MYH6* mutations.
- **Epileptic encephalopathies**: *KCNQ2*, *SCN1A*, *CDKL5* mutations.

Diagnosis is established by identification of biallelic pathogenic variants in *GNB5* on molecular genetic testing. The presence of sinus node dysfunction in a child with neurodevelopmental delay should prompt consideration of *GNB5* sequencing [1, 4].

### 4.4 The flailer Mouse Model

The flailer (flr) mouse mutant, caused by exon shuffling between *Gnb5* and *Myo5a*, exhibits severe ataxia, tremor, and juvenile lethality [17]. This model has been instrumental in establishing the role of Gβ5 in motor coordination and cerebellar development. The hybrid gene produces a chimeric protein with disrupted function, leading to Purkinje cell degeneration and impaired synaptic transmission.

---

## 5. Host-Pathogen & Viral Interactions

### 5.1 Viral Modulation of Gβ5 Expression

The role of *GNB5* in host-pathogen interactions is an emerging area of research. Transcriptomic analyses have identified *GNB5* as a differentially expressed gene in response to viral infections:

- **Porcine Reproductive and Respiratory Syndrome Virus (PRRSV)**: In porcine alveolar macrophages, *GNB5* expression is altered upon PRRSV infection, suggesting a role in the host antiviral response [9]. The modulation of GPCR signaling by Gβ5 may influence cytokine production and immune cell activation.

- **Influenza and other respiratory viruses**: Bioinformatic analyses of gene expression changes associated with isoflurane anesthesia and neurocognitive disorders have identified *GNB5* as a hub gene, though the direct viral interaction remains speculative [10].

### 5.2 Bacterial Effectors and Immune Evasion

The CX3CL1-CX3CR1 axis, which is modulated by GNB5, plays a role in inflammatory responses. Allocryptopine, an isoquinoline alkaloid, exerts anti-inflammatory effects by targeting the CX3CL1-CX3CR1/GNB5/AKT/NF-κB pathway [5]. This suggests that bacterial pathogens or their metabolites could potentially manipulate Gβ5 signaling to evade immune clearance, though direct evidence is lacking.

### 5.3 Parasitic Interactions

In a genome-wide protein interaction analysis of parasitic flatworms (*Gyrodactylus* spp.) and their fish hosts, *GNB5* was identified as a potential host protein targeted by parasite effectors [11]. The Gβ5-R7 complex may be hijacked by parasite proteins to modulate host GPCR signaling and facilitate infection. This represents a novel avenue for antiparasitic drug development.

---

## 6. Pharmacogenomics, Drug Targets & Small-Molecule Inhibitors

### 6.1 Therapeutic Targeting of Gβ5

The diverse functions of Gβ5 make it an attractive therapeutic target for multiple diseases:

- **Alzheimer's Disease**: Upregulation of Gβ5 or stabilization of the Gβ5-R7 complex could reduce BACE1-mediated Aβ production. Small molecules that enhance Gβ5-BACE1 interaction or promote BACE1 degradation are under investigation [6]. Gene therapy approaches using AAV vectors to deliver *GNB5* to the brain are also being explored in preclinical models.

- **Type 2 Diabetes**: The Gβ5-R7 complex potentiates M3R-stimulated insulin secretion. Pharmacological agents that enhance Gβ5-R7 activity in pancreatic β-cells could improve glucose-stimulated insulin release. Allocryptopine, which targets the GNB5/AKT/NF-κB pathway, has shown anti-inflammatory effects in colitis models and may have metabolic benefits [5].

- **Cardiac Arrhythmias**: In IDDCA, the loss of Gβ5 leads to sinus node dysfunction. Gene therapy to restore Gβ5 expression in the sinoatrial node could potentially correct bradycardia. Alternatively, drugs that bypass the Gβ5-dependent pathway, such as direct GIRK channel modulators, may be beneficial [19].

- **Cancer**: The ITGB4/GNB5 axis promotes M2 macrophage reprogramming and NSCLC metastasis. Targeting this axis with monoclonal antibodies against ITGB4 or small-molecule inhibitors of Gβ5 could inhibit tumor metastasis [8, 12]. M2pep-modified liposomal nanoparticles delivering siITGB4 have shown promise in preclinical models [12].

### 6.2 Investigational Compounds

| **Compound** | **Mechanism** | **Disease** | **Stage** |
|---|---|---|---|
| Allocryptopine | Targets CX3CL1-CX3CR1/GNB5/AKT/NF-κB | IBD, inflammation | Preclinical [5] |
| siITGB4 (M2pep-LNP) | Silences ITGB4, disrupts GNB5 axis | NSCLC metastasis | Preclinical [12] |
| Gβ5-stabilizing peptides | Enhance Gβ5-R7 complex stability | AD, diabetes | Research [6] |
| RGS9 inhibitors | Modulate Gβ5-RGS9 GAP activity | Parkinson's disease, addiction | Research [13] |

### 6.3 Pharmacogenomic Considerations

Genetic variation in *GNB5* may influence drug response. For example, the hypomorphic allele c.628-6G>A affects splicing efficiency and could alter the expression of Gβ5 in tissues, potentially impacting the efficacy of drugs that target GPCR signaling pathways [6]. Additionally, *GNB5* expression levels have been correlated with response to cetuximab in colorectal cancer, suggesting that Gβ5 could serve as a predictive biomarker for EGFR-targeted therapy [14].

---

## 7. Bioinformatic Resources & Database Accessions

| **Database** | **Accession/ID** | **URL** |
|---|---|---|
| NCBI Gene | 10627 | https://www.ncbi.nlm.nih.gov/gene/10627 |
| Ensembl | ENSG00000079931 | https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000079931 |
| UniProt | O14775 | https://www.uniprot.org/uniprotkb/O14775 |
| RCSB PDB | 2BCJ, 4F8L | https://www.rcsb.org/structure/2BCJ |
| OMIM | 604447 (gene), 617814 (IDDCA) | https://www.omim.org/entry/604447 |
| ClinVar | GNB5 | https://www.ncbi.nlm.nih.gov/clinvar/?term=GNB5 |
| GeneCards | GC15M052447 | https://www.genecards.org/cgi-bin/carddisp.pl?gene=GNB5 |
| STRING | 10627 (Homo sapiens) | https://string-db.org/network/9606.ENSP00000262047 |
| BioGRID | 112590 | https://thebiogrid.org/112590 |
| GTEx Portal | GNB5 | https://gtexportal.org/home/gene/GNB5 |
| Human Protein Atlas | ENSG00000079931 | https://www.proteinatlas.org/ENSG00000079931-GNB5 |

### Gene Ontology (GO) Terms

| **Category** | **GO Term** | **Accession** |
|---|---|---|
| Molecular Function | GTPase activator activity | GO:0005096 |
| Molecular Function | Signal transducer activity | GO:0004871 |
| Molecular Function | Protein binding | GO:0005515 |
| Biological Process | G protein-coupled receptor signaling pathway | GO:0007186 |
| Biological Process | Regulation of insulin secretion | GO:0050796 |
| Biological Process | Nervous system development | GO:0007399 |
| Cellular Component | Cytoplasm | GO:0005737 |
| Cellular Component | Plasma membrane | GO:0005886 |

---

## Related Clinical & Scientific Guides

* [IRF6 Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/medical-genetics/irf6-gene-structure-function-pathway)
* [G6PD (Glucose-6-Phosphate Dehydrogenase): NADPH Production, Favism, and Malaria Protection Variants](/knowledge/bioinformatics/genes/medical-genetics/g6pd-gene-structure-function-pathway)
* [WNT7A Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/medical-genetics/wnt7a-gene-structure-function-pathway)

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