Localized mRNA translation mediated by Staufen is a novel mechanism regulating cytoskeletal reorganization in response to podocyte injury.. Mus musculus

Podocyte injury that compromises the glomerular filtration barrier is an initiating feature of chronic kidney disease. Podocytes extend major cytoplasmic projections that ultimately subdivide into interdigitating foot processes to form a scaffold that supports the glomerular filtration barrier. We investigated whether podocytes, like other cell types that elaborate complex cytoplasmic projections, utilize RNA transport and local translation in order to synthesize proteins at sites distal from the cell body. Here we show that mice deficient in the RNA binding proteins Staufen1 and 2 are significantly more sensitive to podocyte injury. Furthermore, Staufen2 associates with the podocyte cytoskeleton and is present in foot processes. After injury, Staufen2 and translating ribosomes increase markedly in areas of effacement adjacent to the glomerular basement membrane. Lastly, we found that Staufen2-bound RNAs are enriched in those encoding proteins mediating cytoskeletal assembly and cell-matrix adhesion. RNA transport and localized translation is identified as a crucial process for maintaining the glomerular filtration barrier. Overall design: Pairwise comparison of two sample classes (control/input versus Staufen 2 RNA-IP) with 3 replicates per class.