Figure 3.

Composite summary of the most prominent factors and signals involved in the regulation of erythro-thrombopoiesis. Erythroid signals are in red, thrombocytic signals are in blue, and signals involved in both differentiation pathways are depicted in black. Human TPO ligand and TPOR are shown in blue; human EPO and EPOR are shown in red. Tyrosine residues (Y, pink lines) in TPOR/EPOR intracellular domains important for receptor signaling are shown. Some of them are highly conserved throughout the vertebrate species as demonstrated in the table. Cytokines' signal peptides are in black and EPO/TPO domains are shown. Receptors' WSXSW motifs are in grey and squared boxes represent Box1/Box2. Cs represent conserved Cys residues; ∗s represent glycosylation sites.