VNN1
Description
The VNN1 (vanin 1) is a protein-coding gene located on chromosome 6.
The VNN1 gene encodes for Pantetheinase, an enzyme belonging to the Vanin family of proteins. Vanin proteins share extensive sequence similarity with each other and with biotinidase. While the family includes secreted and membrane-associated proteins, some of which have been linked to hematopoietic cell trafficking, no biotinidase activity has been demonstrated for any vanin protein. However, they all possess pantetheinase activity, potentially contributing to oxidative-stress response. Similar to its mouse counterpart, VNN1 is likely a GPI-anchored cell surface molecule. The mouse VNN1 protein is expressed by perivascular thymic stromal cells and regulates the migration of T-cell progenitors to the thymus. Notably, the VNN1 gene is positioned close to, and in the same transcriptional orientation as two other vanin genes on chromosome 6q23-q24.
VNN1 hydrolyzes one of the carboamide linkages in D-pantetheine, recycling pantothenic acid (vitamin B5) and releasing cysteamine. This activity is supported by experimental evidence.
VNN1 is also known as HDLCQ8, Tiff66.
Associated Diseases
- isolated asymptomatic elevation of creatine phosphokinase
- acute kidney failure
- Parkinson disease
- progressive supranuclear palsy-pure akinesia with gait freezing syndrome
- Bartsocas-Papas syndrome 1