Origins of the Vertebrate Erythro/Megakaryocytic System

Figure 5

The common ancestral erythro-thrombocytic model predicts the existence of unilineage differentiation in ancestral vertebrates, leading to ancient erythroid or thrombocytic cells or erythro-thrombocytic cells with dual function. Hypothetical duplication of cell types and their signalosomes led to the origin of erythrocytes with EPO signaling and to the origin of thrombocytes together with TPO signaling.