In the images are developing vascular network (red) in the mouse yolk sac and an extracellular matrix protein named tenascin-R that is expressed along these vessels (green). Here, a remodeled and large vessel is pictured, overlaying a network of immature vessels.
My research project aimed to understand the extracellular matrix environment that is important for blood vessel formation early in development. The yolk sac is the first place that blood vessels are formed; blood cells formed in the yolk sac and yolk sac vasculature are necessary during development of the embryo before the embryo starts to produce its own blood cells. The tenascin-R protein, which has only been observed in the central nervous system, is assembled into fibers along the track of blood vessels in the yolk sac, suggesting a potential novel role of tenascin-R in blood vessel formation.