C-terminal domains of VEGF-A dictate its biological properties

VEGF-A is a crucial growth factor for blood vessels homeostasis and pathological angiogenesis. It is produced under different isoforms resulting from a dynamic mechanism of alternative splicing affecting the 3'-half of its primary transcript. Although the implicated protein domains are not involved in binding to its receptors, they strongly influence the VEGF biological activity by regulating its availability, structure and affinity for co-receptors. This work aimed at a better understanding of the functions and the cooperation between the C-terminal domains of VEGF-A as controversies still exist about their specific roles, especially the antiangiogenic function of the exon 8b-derived sequence. We engineered 8 different expression constructs all containing the sequences of exons 1-4 followed by various combinations of exons 5, 7 and 8a or b. We tested their properties in several models in vitro and in vivo. The experiments described in this manuscript allow us to decipher the role of the C-terminal domain of VEGF-A in receptors binding, angiogenesis and cancerd development.