Loss of RNA-Binding Protein HuR Leads to Defective Ependymal Cells and Hydrocephalus.

Multiciliated ependymal cells line the ventricle wall and generate CSF flow through ciliary beating. Defects in ependymal cells cause hydrocephalus; however, there are still significant gaps in our understanding the molecular, cellular and developmental mechanisms involved in the pathogenesis of hydrocephalus. Here, we demonstrate that specific deletion of RNA-binding protein (RBP) Hu antigen R (HuR) in the mouse brain results in hydrocephalus and causes postnatal death. HuR deficiency leads to impaired ependymal cell development with defective motile ciliogenesis in both female and male mice. Transcriptome-wide analysis reveals that HuR binds to mRNA transcripts related to ciliogenesis, including cilia and flagella associated protein 52 (Cfap52), the effector gene of Foxj-1 and Rfx transcriptional factors. HuR deficiency accelerates the degradation of Cfap52 mRNA, while overexpression of Cfap52 is able to promote the development of HuR-deficient ependymal cells. Taken together, our results unravel the important role of HuR in posttranscriptional regulation of ependymal cell development by stabilizing Cfap52 mRNA.SIGNIFICANCE STATEMENT This study identifies Hu antigen R (HuR) as a genetic factor involved in the pathogenesis of hydrocephalus. Mechanistically, HuR regulates ependymal cell differentiation and ciliogenesis through stabilizing Cfap52 mRNA, the effector gene of Foxj-1 and Rfx transcriptional factors.