Expression Of IFNLR1 In The Inner Ear Of Mouse And Phenotypic And Functional Analysis Of The Ifnlr1-knockdown Zebrafish

ObjectiveHearing loss is the most common neurosensory disorders primarily originating from genetic etiologies and clinically occurring without any additional phenotype.Non-syndromic hereditary forms are the most common disorders and known to be genetically heterogeneous.We have identified a mutation c.296G>A(p.Arg99His)in IFNLR1 gene in a large Chinese ADNSHL family by whole exome sequencing.In order to clarify the relationship between IFNLR1 and inner ear and to further study the function of the gene,this study conducted relevant exploration based on animal models.Methods(1)To identify and localize the expression of Ifnlr1 in the inner ear of mice using western blot and immunofluorescence staining;(2)To build the ifnlr1-knockdown model of zebrafish using morpholino oligonucleotide technology and to observe the general status and the situation of the lateral line system of the mutant zebrafish in different stages,as well as the apoptosis and the migration of macrophages,(3)To analyze the function of ifnlr1 gene in m RNA level by performing transcriptome sequencing technology in zebrafish.Results(1)The Ifnlr1 gene is widely expressed in the cochlea of mouse,especially in the hair cells and supporting cells of Corti’s organ as well as the spiral ganglion;(2)Abnormalities of general phenotype showed up in the late development of the ifnlr1-knockdown zebrafishes showed up in the late development general phenotypic abnormalities.The neuromasts,hair cells andsupporting cells decreased in number.Apoptosis experiment and macrophage migration experiment showed no specific performance;(3)RNA-Seq analysis revealed many differentially expressed genes,and the GO functional analysis and KEGG pathway function analysis of these genes were found in the detailed data.ConclusionsIFNLR1,as a new gene for deafness,has been identified expressed in the cochlea of mouse and is clearly expressed in the inner hair cells and the spiral ganglion,which are associated with sensorineural deafness.Decreased number of neuromasts,hair cells and supporting cells were identified in the ifnlr1-knockdown zebrafish model,the cause of the affect may have nothing to do with apoptosis and inflammatory reaction and related mechanism remains to be further discussed.