FAM134B (Family With Sequence Similarity 134 Member B) is a retroviral receptor-like protein involved in endoplasmic reticulum turnover through reticulophagy. FAM134B plays a critical role in ER quality control and is associated with hereditary sensory and autonomic neuropathy (HSAN2), highlighting its importance in neuronal survival.
| FAM134B (RETREG1) | |
|---|---|
| Gene Symbol | FAM134B |
| Full Name | Family With Sequence Similarity 134 Member B (Retregulin) |
| Chromosome | 5p15.1 |
| NCBI Gene ID | 54494 |
| OMIM | 613374 |
| Ensembl ID | ENSG00000144136 |
| UniProt ID | Q9H6Y3 |
| Associated Diseases | Hereditary Sensory and Autonomic Neuropathy Type II, Parkinson's Disease |
FAM134B (also known as RETREG1) encodes an ER-phagy receptor crucial for the degradation of ER fragments through autophagy (ER-phagy). This protein localizes to the ER and binds to LC3/GABARAP proteins to deliver ER portions to the autophagosome for degradation. FAM134B-mediated ER-phagy is essential for ER homeostasis, quality control, and the regulation of ER size. In neurons, proper ER-phagy function is important for maintaining ER integrity and clearing damaged ER components, which accumulate in neurodegenerative diseases.
Widely expressed with high levels in neurons. Particularly important in peripheral sensory neurons where loss-of-function causes hereditary sensory neuropathy.
| Disease | Variants | Inheritance | Mechanism |
|---|---|---|---|
| HSAN2A | Loss-of-function | Autosomal Recessive | Impaired ER-phagy, sensory neuron degeneration |
| Parkinson's Disease | Risk variants | Complex | Dysregulated ER-phagy |
| Neurodegeneration | Various | Risk factor | Impaired ER quality control |