Figure 1.

Schematic representation of ectoenzymes expressed on the surface of two different cell types in the bone marrow microenvironment and enzymatic reaction chains with their substrates, involving canonical and noncanonical adenosinergic pathways. Ectoenzymes in black squares and bold arrows indicate the noncanonical pathway, whereas ectoenzymes in blue dotted squares along with dotted arrows indicate the canonical pathway. NADase: nicotinamide adenine dinucleotidase; ADP: adenosine diphosphate; NAD⁺: nicotinamide adenine dinucleotide⁺; Nic: nicotinamide; cADPR: cyclic adenosine diphosphate ribose; ADPR: adenosine diphosphate ribose; PPi: inorganic pyrophosphate; AMP: adenosine monophosphate; ATP: adenosine triphosphate; NPP: nucleotide pyrophosphatase/phosphodiesteras; P1 ADOR: purinergic type 1 adenosine receptor; 5′-NT: 5′-nucleotidase; NTPDase: nucleoside triphosphate diphosphohydrolase.