2.A.1.14.21
The vesicular purine nucleotide (ADP, ATP, GTP) transporter, VNUT or SLC17A9. It is found in synaptic vesicles and chromafin granules (Sawada et al., 2008)) and is associated with disseminated superficial actinic porokeratosis (DSAP), a rare autosomal dominant genodermatosis (Cui et al. 2014). It plays a key role in purinergic signaling through its ability to transport nucleotides using the pmf. It catalyzes Cl^--dependent transport activity involving essential arginines in the transmembrane region. Ketoacids inhibit these transporters through modulation of Cl^- activation, but Cl^- and the arginine residues are not important for ATP binding (Iwai et al. 2019). High expression of SLC17A9 correlates with a poor prognosis for colorectal cancer (Yang et al. 2019).