Af647 conjugated abt

Dechorionated embryos at 50 hpf were soaked in 1X tricaine and immobilized in a 1.5% canyon mount cast filled with egg water. Texas-red Dextran (3 kDa and 70 kDa from Thermo Fisher) and AF647 conjugated α-bungarotoxin protein (aBt, Thermo Fisher ) were dissolved in 1X PBS and stored at 10 mM at −20°C and 1 mM at −80°C, respectively. The injection solution was made with 1X PBS/0.5% Phenol Red. Texas-red Dextran (either 3 kDa or 70 kDa, 500 μM ) was co-injected with AF647 conjugated aBt (Thermo Fisher, 500 μM) into the periotic space (anterior and posterior to the OV). Embryos were imaged at 2 hours post-injection. To measure the Dextran percolation in embryos treated with Chase, Texas-red Dextran (either 3 kDa, 10 kDa, or 70 kDa, 500 μM) and AF647 conjugated aBt (Thermo Fisher, 500 μM) were co-injected with Chase (10 U/mL) into periotic space, followed by imaging of OVs at 2 hours post-injection.