Rab27B Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
| Property |
Value |
| Gene Symbol |
RAB27B |
| Full Name |
RAB27B, Member RAS Oncogene Family |
| Chromosomal Location |
18q21.1 |
| NCBI Gene ID |
26789 |
| Ensembl ID |
ENSG00000167510 |
| UniProt ID |
Q9UQ26 |
| OMIM ID |
605342 |
| Protein Class |
Small GTPase (Rab family) |
| Species |
Human |
| Associated Diseases |
Hermansky-Pudlak Syndrome, Bleeding Disorders, Neurodegeneration, Cancer |
The RAB27B gene encodes a member of the Rab GTPase family involved in regulated secretion and vesicular transport. RAB27B is particularly important for controlling exocytosis in various cell types, including neuroendocrine cells, platelets, melanocytes, and neurons. It plays critical roles in neurotransmitter release, hormone secretion, and lysosome-related organelle function. RAB27B dysfunction is implicated in Hermansky-Pudlak syndrome (a bleeding disorder) and various neurological conditions.
RAB27B is a small GTPase that cycles between active (GTP-bound) and inactive (GDP-bound) states:
- GTP binding: Active state; interacts with effector proteins
- GTP hydrolysis: Inactive state; regulated by GAPs
- Membrane association: Rab escort proteins (REPs) deliver to membranes
- Effector binding: Multiple effectors including Slac2-a, MyRIP, Munc13-4
- Exocytosis control: Regulates vesicle docking, priming, and fusion
Key characteristics:
- Synaptic function: Regulates synaptic vesicle and dense-core vesicle release
- Platelet function: Essential for platelet granule secretion
- Melanocyte function: Controls melanosome transport
- Hormone secretion: Regulates endocrine cell secretion
- Highest: Brain (cerebral cortex, hippocampus), pituitary, adrenal gland
- High expression: Platelets, mast cells, endocrine glands
- Moderate expression: Lung, kidney, spleen
- Low expression: Most other tissues
- Synaptic vesicles: Regulates neurotransmitter release
- Dense-core vesicles: Controls neuropeptide and hormone release
- Secretory granules: Regulates platelet and mast cell secretion
- Melanosomes: Controls pigment granule transport
- Synaptic function: RAB27B regulates synaptic vesicle cycling
- Dopamine release: Affects dopaminergic neuron function
- Protein aggregation: RAB27B may affect protein aggregate clearance
- Therapeutic target: Modulating exocytosis for neuroprotection
- Amyloid secretion: Regulates Aβ release from neurons
- Synaptic plasticity: Affects activity-dependent secretion
- Neuroinflammation: May affect inflammatory mediator release
- Biomarker potential: RAB27B in CSF as a synaptic marker
- Synaptic dysfunction: Altered RAB27B in ALS models
- Neuromuscular junction: Affects neuromuscular transmission
- Exosome release: May regulate toxic protein spread
- Vesicular transport: RAB27B dysfunction in HD
- Neurotransmitter release: Altered GABA and glutamate release
- Therapeutic potential: Targeting RAB27B for HD
- No direct therapeutics: No RAB27B-targeted drugs approved
- Research focus: Understanding role in disease pathogenesis
- Diagnostic potential: RAB27B as a biomarker
- Gene therapy: AAV-delivered RAB27B for deficiency
- Small molecules: Modulators of Rab GTPases
- Biomarkers: RAB27B in CSF or blood
- Combination therapies: With other synaptic targets
- Bleeding disorder: Prolonged bleeding time
- Hypopigmentation: Reduced melanosome transfer
- Neuroendocrine deficits: Impaired hormone secretion
- Learning deficits: Altered synaptic plasticity
- Neuron-specific rescue
- PD model crosses
- Synaptic function studies
- Biomarkers: RAB27B as synaptic biomarker
- Gene therapy: For RAB27B deficiency
- Drug targets: Rab GTPase modulators
- Disease mechanisms: RAB27B in neurodegeneration
The study of Rab27B Gene has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
- PMID:10393812 - Cloning of RAB27B
- PMID:11734219 - RAB27B in platelet secretion
- PMID:14699056 - RAB27B in exocytosis
- PMID:15159431 - RAB27B and neurological function
- PMID:16720733 - RAB27B knockout mice
- PMID:18078701 - RAB27B in neurodegenerative disease
- PMID:21826171 - RAB27B in synaptic plasticity
- PMID:25297554 - Rab GTPases in neurodegeneration