Alternative splicing in mechanically stretched podocytes as a model of glomerular hypertension

Alterations in pre-mRNA splicing play an important role in disease pathophysiology. However, the role of alternative splicing (AS) for podocytes in hypertensive nephropathy (HN) has not been investigated. Here we identifiedAS events that play a role in the development and progression of HN. For this, murine podocytes were exposed to mechanical stretch to model HN, after which proteins and mRNA were measured by proteomics, RNA-Seq, and analyzed by several AS detection tools. We found two Shroom3 isoforms that showed significant changes in expression upon mechanical stretch, which was verified by qRT-PCR and in-situ hybridization. Furthermore, we observed an expression switch of two Myl6 isoforms after mechanical stretch. This switch is accompanied by a change in a C-terminally located amino acid sequence. In summary, mechanical stretch of cultured podocytes is an excellent model to simulate hypertensive nephropathy. In depth RNA-Seq analysis disclosed alternative splicing events and differential gene expression, which together with protein regulation improve the understanding of the pathophysiology of hypertension-induced nephropathy.