Fgf8P2A-3 ×GFP/+: A New Genetic Mouse Model for Specifically Labeling and Sorting Cochlear Inner Hair Cells

AbstractThe cochlear auditory epithelium contains two types of sound receptors, inner hair cells (IHCs) and outer hair cells (OHCs). Mouse models for labelling juvenile and adult IHCs or OHCs exist; however, labelling for embryonic and perinatal IHCs or OHCs are lacking. Here, we generated a new knock-inFgf8P2A-3 ×GFP/+ (Fgf8GFP/+) strain, in which the expression of a series of three GFP fragments is controlled by endogenousFgf8 cis-regulatory elements. After confirming that GFP expression accurately reflects the expression ofFgf8, we successfully obtained both embryonic and neonatal IHCs with high purity, highlighting the power ofFgf8GFP/+. Furthermore, our fate-mapping analysis revealed, unexpectedly, that IHCs are also derived from inner ear progenitors expressingInsm1, which is currently regarded as an OHC marker. Thus, besides serving as a highly favorable tool for sorting early IHCs,Fgf8GFP/+ will facilitate the isolation of pure early OHCs by excluding IHCs from the entire hair cell pool.

Source: Neuroscience Bulletin - May 26, 2023 Category: Neuroscience Source Type: research