Integrin-β1 is required for the renal cystogenesis caused by ciliary defects.

Defects in the function of primary cilia are commonly associated with the development of renal cysts. On the other hand, the intact cilium appears to contribute a cystogenic signal whose effectors remain unclear. As integrin-β1 is required for the cystogenesis caused by the deletion of the polycystin 1 gene, we asked whether it would be similarly important in the cystogenetic process caused by other ciliary defects. We addressed this question by investigating the effect of integrin-β1 deletion in a ciliopathy genetic model in which the Ift88 gene, a component of complex B of intraflagellar transport that is required for the proper assembly of cilia, is specifically ablated in principal cells of the collecting ducts. We showed that the renal cystogenesis caused by loss of Ift88 is prevented when integrin-β1 is simultaneously depleted. In parallel, pathogenetic manifestations of the disease, such as increased inflammatory infiltrate and fibrosis, were also significantly reduced. Overall, our data indicate that integrin-β1 is also required for the renal cystogenesis caused by ciliary defects and point to integrin-β1-controlled pathways as common drivers of the disease and as possible targets to interfere with the cystogenesis caused by ciliary defects.