Purinergic signalling Nucleoside transporters Ectonucleotidases consist of families of nucleotide metabolizing enzymes that are expressed on the plasma membrane and have externally oriented active sites.
The contribution of ectonucleotidases in the modulation of purinergic signaling depends on the availability and preference of substrates and on cell and tissue distribution.
[1] Subfamilies of ectonucleotidases include: CD39/NTPDases (ecto-nucleotide triphosphate diphosphohydrolases), Nucleotide pyrophosphatase/phosphodiesterase (NPP)-type ecto-phosphodiesterases, alkaline phosphatases and ecto-5’-nucleotidases/CD73.
[1] Ectonucleotidases produce key molecules for purine salvage and consequent replenishment of ATP stores within multiple cell types.
Dephosphorylated nucleoside derivatives interact with membrane transporters to enable intracellular uptake.