STX3
Function
Potentially involved in docking of synaptic vesicles at presynaptic active zones. Apical receptor involved in membrane fusion of apical vesicles.
Isoform B
Essential for survival of retinal photoreceetors.
Isoform 3
Functions as a regulator of gene expression.
Involvement in disease
Retinal dystrophy and microvillus inclusion disease
RDMVID
An autosomal recessive disease characterized by early-onset, severe retinal dystrophy associated with intractable congenital diarrhea. Intestinal biopsies show loss of microvilli, microvillus inclusions, and accumulation of subapical vesicles in villus enterocytes.
None
The disease is caused by variants affecting the gene represented in this entry.
Diarrhea 12, with microvillus atrophy
DIAR12
An autosomal recessive congenital enteropathy characterized by intractable secretory diarrhea, resulting in severe dehydration and metabolic acidosis. DIAR12 can be diagnosed based on variable loss of brush-border microvilli, microvillus inclusions, and accumulation of subapical vesicles in villus enterocytes.
None
The disease is caused by variants affecting the gene represented in this entry.
Sequence Similarities
Belongs to the syntaxin family.
Tissue Specificity
Isoform A
Expressed in small intestine, kidney, pancreas, placenta as well as in retina. Weaker expression in lung, liver and heart. Not expressed in brain and skeletal muscle.
Isoform B
Expressed only in the retina.
Isoform 3
Ubiquitously expressed.
Cellular localization
- Isoform A
- Apical cell membrane
- Single-pass type IV membrane protein
- Localized to the inner and outer plexiform layers, the cell body and the inner segments of photoreceptors.
- Isoform 3
- Nucleus
Alternative names
STX3A, STX3, Syntaxin-3