Fig. 6

Functional studies of SCUBE family using the zebrafish model. A Scube1 and Scube2 from zebrafish endothelial cells work together to support Vegfa signaling during embryonic vascularization. Endothelial Scube1 and Scube2 form a complex under physiological conditions, such as during the development of embryonic vessels. This complex may promote Vegf-induced Vegfr2 phosphorylation and its downstream signaling for proper vasculogenesis and angiogenesis [130]. B Zebrafish Scube3 acts as an Fgf coreceptor during fast muscle fiber development. We utilized a combination of molecular, biochemical, and genetic methods to reveal a new biological function for SCUBE3 as a key regulator of fast muscle precursors. SCUBE3 potentially acts as a coreceptor at the plasma membrane to promote Fgf8 signaling for the differentiation of fast muscle precursors in zebrafish [9]