RESUMO
While the mouse has been a productive model for inner ear studies, a lack of highly specific genes and tools has presented challenges. The absence of definitive otic lineage markers and tools is limiting in vitro studies of otic development, where innate cellular heterogeneity and disorganization increase the reliance on lineage-specific markers. To address this challenge in mice and embryonic stem (ES) cells, we targeted the lineage-specific otic gene Fbxo2 with a multicistronic reporter cassette (Venus/Hygro/CreER = VHC). In otic organoids derived from ES cells, Fbxo2VHC specifically delineates otic progenitors and inner ear sensory epithelia. In mice, Venus expression and CreER activity reveal a cochlear developmental gradient, label the prosensory lineage, show enrichment in a subset of type I vestibular hair cells, and expose strong expression in adult cerebellar granule cells. We provide a toolbox of multiple spectrally distinct reporter combinations for studies that require use of fluorescent reporters, hygromycin selection, and conditional Cre-mediated recombination.
Assuntos
Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Orelha Interna/embriologia , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Animais , Linhagem da Célula , Cóclea/embriologia , Cóclea/metabolismo , Orelha Interna/metabolismo , Células-Tronco Embrionárias/fisiologia , Epitélio/metabolismo , Gânglios Parassimpáticos , Engenharia Genética/métodos , Humanos , Imuno-Histoquímica/métodos , Integrases , Camundongos , Camundongos Transgênicos , TamoxifenoRESUMO
The mammalian hair follicle arises during embryonic development from coordinated interactions between the epidermis and dermis. It is currently unclear how to recapitulate hair follicle induction in pluripotent stem cell cultures for use in basic research studies or in vitro drug testing. To date, generation of hair follicles in vitro has only been possible using primary cells isolated from embryonic skin, cultured alone or in a co-culture with stem cell-derived cells, combined with in vivo transplantation. Here, we describe the derivation of skin organoids, constituting epidermal and dermal layers, from a homogeneous population of mouse pluripotent stem cells in a 3D culture. We show that skin organoids spontaneously produce de novo hair follicles in a process that mimics normal embryonic hair folliculogenesis. This in vitro model of skin development will be useful for studying mechanisms of hair follicle induction, evaluating hair growth or inhibitory drugs, and modeling skin diseases.
