UNC13B
Description
The UNC13B (unc-13 homolog B) is a protein-coding gene located on chromosome 9.
The UNC13B gene encodes a protein that is highly similar to its rat counterpart. It contains three C2 domains and a diacylglycerol-binding C1 domain. UNC13B is primarily expressed in kidney cortical epithelial cells and its expression is elevated by high blood sugar levels (hyperglycemia). Hyperglycemia increases the levels of diacylglycerol, which can trigger cell death in cells expressing UNC13B. This suggests a role for UNC13B in the kidney complications associated with hyperglycemia. In other species, UNC13B has been shown to be involved in the priming of synaptic vesicles for exocytosis.
UNC13B plays a key role in vesicle maturation during exocytosis, responding to the diacylglycerol signaling pathway. It is involved in neurotransmitter release by priming synaptic vesicles for fusion, contributing to the replenishment of the readily releasable vesicle pool. UNC13B is essential for synaptic vesicle maturation in specific excitatory synapses that utilize glutamate, but not in inhibitory synapses that rely on GABA. In collaboration with UNC13A, UNC13B promotes the fusion of neuronal dense core vesicles and regulates the location and efficiency of their release at synapses.
UNC13B is also known as MUNC13, UNC13, Unc13h2, munc13-2.
Associated Diseases
- thyroid gland adenocarcinoma
- isolated congenital hypogonadotropic hypogonadism
- 46,XX testicular disorder of sex development
- 46,XY complete gonadal dysgenesis
- 46,XY disorder of sex development due to 5-alpha-reductase 2 deficiency
- familial male-limited precocious puberty
- spermatogenic failure, X-linked, 2
- X-linked intellectual disability-macrocephaly-macroorchidism syndrome
- partial chromosome Y deletion
- familial adrenal hypoplasia with absent pituitary luteinizing hormone
- 46,XX ovotesticular disorder of sex development
- spinocerebellar ataxia type 32
- testicular agenesis
