Description
Blood-retina barrier (BRB) formation and retinal angiogenesis depend on beta-catenin signaling induced by the ligand norrin (NDP), the receptor frizzled4 (FZD4), co-receptor LRP5, and the tetraspanin TSPAN12. Impaired NDP/FZD4 signaling causes familial exudative vitreoretinopathy (FEVR), which may lead to blindness. Endothelial-cell specific inactivation of the Tspan12 gene at P28 using a Cdh5-CreERT2 driver shows that TSPAN12 functions in ECs to promote vascular morphogenesis and BRB formation in developing mice, and BRB maintenance in adult mice. 12 month after Tspan12 inactivation and loss of BRB maintenance with massive IgG and albumin extravasation we observe complement activation, cystoid edema, and impaired beta-wave in electroretinograms. RNA-Seq 6 month after Tspan12 inactivation provides a detailed view on the transcriptional response, including activation of antibody effector systems (complement and Fc receptors), inflammation and microglia responses, extracellular matrix organization and remodeling, and other responses. Overall design: Endothelial cell-specific inactivation of floxed Tspan12 was induced at P28 using a Cdh5-CreERT2 driver and total retina RNA (ribodepleted) from 4 control or ECKO retinas (8 samples) was subjected to RNA-Seq 6 months later