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Wang SX, Streit A. Shared features in ear and kidney development - implications for oto-renal syndromes. Dis Model Mech 2024; 17:dmm050447. [PMID: 38353121 PMCID: PMC10886756 DOI: 10.1242/dmm.050447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2024] Open
Abstract
The association between ear and kidney anomalies has long been recognized. However, little is known about the underlying mechanisms. In the last two decades, embryonic development of the inner ear and kidney has been studied extensively. Here, we describe the developmental pathways shared between both organs with particular emphasis on the genes that regulate signalling cross talk and the specification of progenitor cells and specialised cell types. We relate this to the clinical features of oto-renal syndromes and explore links to developmental mechanisms.
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Affiliation(s)
- Scarlet Xiaoyan Wang
- Centre for Craniofacial and Regenerative Biology, King's College London, London SE1 9RT, UK
| | - Andrea Streit
- Centre for Craniofacial and Regenerative Biology, King's College London, London SE1 9RT, UK
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2
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Young CA, Burt E, Munnamalai V. Sensory progenitors influence patterning of the mammalian auditory sensory epithelium. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.13.566920. [PMID: 38014307 PMCID: PMC10680690 DOI: 10.1101/2023.11.13.566920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
During embryonic development Wnt signaling has been shown to influence proliferation and sensory formation in the cochlea. How the dual nature of Wnt signaling is coordinated is unknown. In this study, we define a novel role for a Wnt regulated gene, Mybl2, which was already known to be important for proliferation, in influencing patterning and determining the size of the sensory epithelium in the murine cochlea. Using a quantitative spatial analysis approach and analyzing Mybl2 loss-of-function cochleas, we show that Mybl2 simultaneously specifies the progenitor niche and the size of the sensory domain, and influences the positioning of the medial sensory domain boundary via Jag1 regulation during the mid-gestational stages. Mybl2 conditional knockout resulted in a decrease of proliferation within the progenitor niche. During the late embryonic stages, conditional knockout of Mybl2 produced a wider sensory epithelium across the radial axis with an increase in ectopic inner hair cell formation. These data suggest that Mybl2 -positive progenitors play a role in boundary formation and patterning the sensory epithelium. Summary Statement Mybl2 is a Wnt-regulated gene encoding a transcription factor that is expressed in the cochlear progenitor niche and influences the boundary formation between the niche and the sensory domain during mid-cochlear developmental stages, thereby impacting the size of the sensory epithelium.
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3
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Heilala M, Lehtonen A, Arasalo O, Peura A, Pokki J, Ikkala O, Nonappa, Klefström J, Munne PM. Fibrin Stiffness Regulates Phenotypic Plasticity of Metastatic Breast Cancer Cells. Adv Healthc Mater 2023; 12:e2301137. [PMID: 37671812 DOI: 10.1002/adhm.202301137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 08/18/2023] [Indexed: 09/07/2023]
Abstract
The extracellular matrix (ECM)-regulated phenotypic plasticity is crucial for metastatic progression of triple negative breast cancer (TNBC). While ECM faithful cell-based models are available for in situ and invasive tumors, such as cell aggregate cultures in reconstituted basement membrane and in collagenous gels, there are no ECM faithful models for metastatic circulating tumor cells (CTCs). Such models are essential to represent the stage of metastasis where clinical relevance and therapeutic opportunities are significant. Here, CTC-like DU4475 TNBC cells are cultured in mechanically tunable 3D fibrin hydrogels. This is motivated, as in circulation fibrin aids CTC survival by forming a protective coating reducing shear stress and immune cell-mediated cytotoxicity and promotes several stages of late metastatic processes at the interface between circulation and tissue. This work shows that fibrin hydrogels support DU4475 cell growth, resulting in spheroid formation. Furthermore, increasing fibrin stiffness from 57 to 175 Pa leads to highly motile, actin and tubulin containing cellular protrusions, which are associated with specific cell morphology and gene expression patterns that markedly differ from basement membrane or suspension cultures. Thus, mechanically tunable fibrin gels reveal specific matrix-based regulation of TNBC cell phenotype and offer scaffolds for CTC-like cells with better mechano-biological properties than liquid.
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Affiliation(s)
- Maria Heilala
- Department of Applied Physics, Aalto University, P.O. Box 15100, Aalto, Espoo, FI-00076, Finland
| | - Arttu Lehtonen
- Department of Electrical Engineering and Automation, Aalto University, P.O. Box 12200, Aalto, Espoo, FI-00076, Finland
| | - Ossi Arasalo
- Department of Electrical Engineering and Automation, Aalto University, P.O. Box 12200, Aalto, Espoo, FI-00076, Finland
| | - Aino Peura
- Finnish Cancer Institute and FICAN South, Helsinki University Hospital & Cancer Cell Circuitry Laboratory, Translational Cancer Medicine, Medical Faculty, University of Helsinki, P.O. Box 63 (Haartmaninkatu 8), Helsinki, 00014, Finland
| | - Juho Pokki
- Department of Electrical Engineering and Automation, Aalto University, P.O. Box 12200, Aalto, Espoo, FI-00076, Finland
| | - Olli Ikkala
- Department of Applied Physics, Aalto University, P.O. Box 15100, Aalto, Espoo, FI-00076, Finland
| | - Nonappa
- Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, Tampere, FI-33720, Finland
| | - Juha Klefström
- Finnish Cancer Institute and FICAN South, Helsinki University Hospital & Cancer Cell Circuitry Laboratory, Translational Cancer Medicine, Medical Faculty, University of Helsinki, P.O. Box 63 (Haartmaninkatu 8), Helsinki, 00014, Finland
| | - Pauliina M Munne
- Finnish Cancer Institute and FICAN South, Helsinki University Hospital & Cancer Cell Circuitry Laboratory, Translational Cancer Medicine, Medical Faculty, University of Helsinki, P.O. Box 63 (Haartmaninkatu 8), Helsinki, 00014, Finland
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4
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Mäkelä OJM, Mikkola ML. Mesenchyme governs hair follicle induction. Development 2023; 150:dev202140. [PMID: 37982496 DOI: 10.1242/dev.202140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 10/23/2023] [Indexed: 11/21/2023]
Abstract
Tissue interactions are essential for guiding organ development and regeneration. Hair follicle formation relies on inductive signalling between two tissues, the embryonic surface epithelium and the adjacent mesenchyme. Although previous research has highlighted the hair-inducing potential of the mesenchymal component of the hair follicle - the dermal papilla and its precursor, the dermal condensate - the source and nature of the primary inductive signal before dermal condensate formation have remained elusive. Here, we performed epithelial-mesenchymal tissue recombination experiments using hair-forming back skin and glabrous plantar skin from mouse embryos to unveil that the back skin mesenchyme is inductive even before dermal condensate formation. Moreover, the naïve, unpatterned mesenchyme was sufficient to trigger hair follicle formation even in the oral epithelium. Building on previous knowledge, we explored the hair-inductive ability of the Wnt agonist R-spondin 1 and a Bmp receptor inhibitor in embryonic skin explants. Although R-spondin 1 instigated precocious placode-specific transcriptional responses, it was insufficient for hair follicle induction, either alone or in combination with Bmp receptor inhibition. Our findings pave the way for identifying the hair follicle-inducing cue.
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Affiliation(s)
- Otto J M Mäkelä
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Sciences (HiLIFE), University of Helsinki, 00014 Helsinki, Finland
| | - Marja L Mikkola
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Sciences (HiLIFE), University of Helsinki, 00014 Helsinki, Finland
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5
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Van Greenen JD, Hockman D. FGF20. Differentiation 2023:100737. [PMID: 38007375 DOI: 10.1016/j.diff.2023.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/25/2023] [Accepted: 10/24/2023] [Indexed: 11/27/2023]
Abstract
Fibroblast growth factor 20 (FGF20) is a neurotrophic factor and a member of the FGF9 subfamily. It was first identified in Xenopus embryos and was isolated shortly thereafter from the adult rat brain. Its receptors include FGFR4, FGFR3b, FGFR2b and the FGFRc splice forms. In adults it is highly expressed in the brain, while it is expressed in a variety of regions during embryonic development, including the inner ear, heart, hair placodes, mammary buds, dental epithelium and limbs. As a result of its wide-spread expression, FGF20 mouse mutants exhibit a variety of phenotypes including congenital deafness, lack of hair, small kidneys and delayed mammary ductal outgrowth. FGF20 is also associated with human diseases including Parkinson's Disease, cancer and hereditary deafness.
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Affiliation(s)
- Justine D Van Greenen
- Division of Cell Biology, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa; Neuroscience Institute, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Dorit Hockman
- Division of Cell Biology, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa; Neuroscience Institute, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
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6
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Sulic AM, Das Roy R, Papagno V, Lan Q, Saikkonen R, Jernvall J, Thesleff I, Mikkola ML. Transcriptomic landscape of early hair follicle and epidermal development. Cell Rep 2023; 42:112643. [PMID: 37318953 DOI: 10.1016/j.celrep.2023.112643] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 04/04/2023] [Accepted: 05/29/2023] [Indexed: 06/17/2023] Open
Abstract
Morphogenesis of ectodermal organs, such as hair, tooth, and mammary gland, starts with the formation of local epithelial thickenings, or placodes, but it remains to be determined how distinct cell types and differentiation programs are established during ontogeny. Here, we use bulk and single-cell transcriptomics and pseudotime modeling to address these questions in developing hair follicles and epidermis and produce a comprehensive transcriptomic profile of cellular populations in the hair placode and interplacodal epithelium. We report previously unknown cell populations and marker genes, including early suprabasal and genuine interfollicular basal markers, and propose the identity of suprabasal progenitors. By uncovering four different hair placode cell populations organized in three spatially distinct areas, with fine gene expression gradients between them, we posit early biases in cell fate establishment. This work is accompanied by a readily accessible online tool to stimulate further research on skin appendages and their progenitors.
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Affiliation(s)
- Ana-Marija Sulic
- Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland
| | - Rishi Das Roy
- Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland
| | - Verdiana Papagno
- Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland
| | - Qiang Lan
- Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland
| | - Riikka Saikkonen
- Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland
| | - Jukka Jernvall
- Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland; Department of Geosciences and Geography, University of Helsinki, 00014 Helsinki, Finland
| | - Irma Thesleff
- Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland
| | - Marja L Mikkola
- Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland.
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7
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Willet SG, Thanintorn N, McNeill H, Huh SH, Ornitz DM, Huh WJ, Hoft SG, DiPaolo RJ, Mills JC. SOX9 Governs Gastric Mucous Neck Cell Identity and Is Required for Injury-Induced Metaplasia. Cell Mol Gastroenterol Hepatol 2023; 16:325-339. [PMID: 37270061 PMCID: PMC10444955 DOI: 10.1016/j.jcmgh.2023.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 05/26/2023] [Accepted: 05/26/2023] [Indexed: 06/05/2023]
Abstract
BACKGROUND & AIMS Acute and chronic gastric injury induces alterations in differentiation within the corpus of the stomach called pyloric metaplasia. Pyloric metaplasia is characterized by the death of parietal cells and reprogramming of mitotically quiescent zymogenic chief cells into proliferative, mucin-rich spasmolytic polypeptide-expressing metaplasia (SPEM) cells. Overall, pyloric metaplastic units show increased proliferation and specific expansion of mucous lineages, both by proliferation of normal mucous neck cells and recruitment of SPEM cells. Here, we identify Sox9 as a potential gene of interest in the regulation of mucous neck and SPEM cell identity in the stomach. METHODS We used immunostaining and electron microscopy to characterize the expression pattern of SRY-box transcription factor 9 (SOX9) during murine gastric development, homeostasis, and injury in homeostasis, after genetic deletion of Sox9 and after targeted genetic misexpression of Sox9 in the gastric epithelium and chief cells. RESULTS SOX9 is expressed in all early gastric progenitors and strongly expressed in mature mucous neck cells with minor expression in the other principal gastric lineages during adult homeostasis. After injury, strong SOX9 expression was induced in the neck and base of corpus units in SPEM cells. Adult corpus units derived from Sox9-deficient gastric progenitors lacked normal mucous neck cells. Misexpression of Sox9 during postnatal development and adult homeostasis expanded mucous gene expression throughout corpus units including within the chief cell zone in the base. Sox9 deletion specifically in chief cells blunts their reprogramming into SPEM. CONCLUSIONS Sox9 is a master regulator of mucous neck cell differentiation during gastric development. Sox9 also is required for chief cells to fully reprogram into SPEM after injury.
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Affiliation(s)
- Spencer G Willet
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri.
| | - Nattapon Thanintorn
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri
| | - Helen McNeill
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri
| | - Sung-Ho Huh
- Department of Otolaryngology-Head and Neck Surgery, University of Mississippi Medical Center, Jackson, Mississippi
| | - David M Ornitz
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri
| | - Won Jae Huh
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut
| | - Stella G Hoft
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, Missouri
| | - Richard J DiPaolo
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, Missouri
| | - Jason C Mills
- Section of Gastroenterology, Department of Medicine, Pathology and Immunology, Baylor College of Medicine, Houston, Texas; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas.
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8
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Song H, Morrow BE. Tbx2 and Tbx3 regulate cell fate progression of the otic vesicle for inner ear development. Dev Biol 2023; 494:71-84. [PMID: 36521641 PMCID: PMC9870991 DOI: 10.1016/j.ydbio.2022.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/05/2022] [Accepted: 12/10/2022] [Indexed: 12/14/2022]
Abstract
The morphogenesis of the otic vesicle (OV) to form inner ear organs serves as an excellent model system to understand cell fate acquisition on a single cell level. Tbx2 and Tbx3 (Tbx2/3) encode closely related T-box transcription factors that are expressed widely in the mammalian OV. Inactivation of both genes in the OV (Tbx2/3cKO) results in failed morphogenesis into inner ear organs. To understand the basis of these defects, single cell RNA-sequencing (scRNA-seq) was performed on the OV lineage, in controls versus Tbx2/3cKO embryos. We identified a multipotent population termed otic progenitors in controls that are marked by expression of the known otic placode markers Eya1, Sox2, and Sox3 as well as new markers Fgf18, Cxcl12, and Pou3f3. The otic progenitor population was increased three-fold in Tbx2/3cKO embryos, concomitant with dysregulation of genes in these cells as well as reduced progression to more differentiated states of prosensory and nonsensory cells. An ectopic neural population of cells was detected in the posterior OV of Tbx2/3cKO embryos but had reduced maturation to delaminated neural cells. As all three cell fates were affected in Tbx2/3cKO embryos, we suggest that Tbx2/3 promotes progression of multipotent otic progenitors to more differentiated cell types in the OV.
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Affiliation(s)
- Hansoo Song
- Department of Genetics, Albert Einstein College of Medicine, 1301 Morris Park Ave., Bronx, NY, USA
| | - Bernice E Morrow
- Department of Genetics, Albert Einstein College of Medicine, 1301 Morris Park Ave., Bronx, NY, USA.
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9
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Kaiser M, Lüdtke TH, Deuper L, Rudat C, Christoffels VM, Kispert A, Trowe MO. TBX2 specifies and maintains inner hair and supporting cell fate in the Organ of Corti. Nat Commun 2022; 13:7628. [PMID: 36494345 PMCID: PMC9734556 DOI: 10.1038/s41467-022-35214-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 11/21/2022] [Indexed: 12/13/2022] Open
Abstract
The auditory function of the mammalian cochlea relies on two types of mechanosensory hair cells and various non-sensory supporting cells. Recent studies identified the transcription factors INSM1 and IKZF2 as regulators of outer hair cell (OHC) fate. However, the transcriptional regulation of the differentiation of inner hair cells (IHCs) and their associated inner supporting cells (ISCs) has remained enigmatic. Here, we show that the expression of the transcription factor TBX2 is restricted to IHCs and ISCs from the onset of differentiation until adulthood and examine its function using conditional deletion and misexpression approaches in the mouse. We demonstrate that TBX2 acts in prosensory progenitors as a patterning factor by specifying the inner compartment of the sensory epithelium that subsequently gives rise to IHCs and ISCs. Hair cell-specific inactivation or misexpression causes transdifferentiation of hair cells indicating a cell-autonomous function of TBX2 in inducing and maintaining IHC fate.
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Affiliation(s)
- Marina Kaiser
- grid.10423.340000 0000 9529 9877Institute of Molecular Biology, Hannover Medical School, Hannover, Germany
| | - Timo H. Lüdtke
- grid.10423.340000 0000 9529 9877Institute of Molecular Biology, Hannover Medical School, Hannover, Germany
| | - Lena Deuper
- grid.10423.340000 0000 9529 9877Institute of Molecular Biology, Hannover Medical School, Hannover, Germany
| | - Carsten Rudat
- grid.10423.340000 0000 9529 9877Institute of Molecular Biology, Hannover Medical School, Hannover, Germany
| | - Vincent M. Christoffels
- grid.509540.d0000 0004 6880 3010Medical Biology, Amsterdam Reproduction & Development, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Andreas Kispert
- grid.10423.340000 0000 9529 9877Institute of Molecular Biology, Hannover Medical School, Hannover, Germany
| | - Mark-Oliver Trowe
- grid.10423.340000 0000 9529 9877Institute of Molecular Biology, Hannover Medical School, Hannover, Germany
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10
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Guo K, Wang L, Zhong Y, Gao S, Jing R, Ye J, Zhang K, Fu M, Hu Z, Zhao W, Xu N. Cucurbitacin promotes hair growth in mice by inhibiting the expression of fibroblast growth factor 18. ANNALS OF TRANSLATIONAL MEDICINE 2022; 10:1104. [PMID: 36388783 PMCID: PMC9652544 DOI: 10.21037/atm-22-4423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 10/08/2022] [Indexed: 08/03/2023]
Abstract
BACKGROUND The inhibition of fibroblast growth factor 18 (FGF18) promotes the transition of hair follicles (HFs) from the telogen phase to the anagen phase. Cucurbitacin has been shown to have a good effect in promoting hair cell growth. This study explored the potential effect of cucurbitacin on hair growth and its effect on FGF18 expression in mice. METHODS Male C57BL/6J mice were randomly divided into the following two groups: (I) the vehicle group; and (II) the cucurbitacin group. Matrix cream and cucurbitacin cream were applied to the depilated skin on the back of the vehicle group mice and the cucurbitacin group mice, respectively. On days 3, 6, 9, 12, 15, and 18, the hair growth in the depilated dorsal skin of the mice was recorded with a digital camera and a HF detector, and the HF cycle status of the mice was observed by hematoxylin and eosin (H&E) staining. In addition, the level of FGF18 messenger ribonucleic acid (mRNA) in the dorsal skin was measured on days 15 and 18 by quantitative real-time polymerase chain reaction (qRT-PCR), while the level of FGF18 protein was measured by western blot and immunofluorescence staining. RESULTS The dorsal skin to which the cucurbitacin cream was applied began to darken on day 6 and grew hairs on day 9, which was 3 days earlier than the dorsal skin to which the matrix cream was applied. The H&E staining revealed a transition from the telogen phase to the anagen phase 3 days earlier for the cucurbitacin cream-treated skin than the matrix cream-treated skin. In addition, the skin treated with cucurbitacin cream also showed a significant decrease in FGF18 mRNA as seen by qRT-PCR, and reduced FGF18 protein levels as detected by western blot and immunofluorescence staining compared to the skin treated with matrix cream only. CONCLUSIONS Cucurbitacin significantly reduced the levels of FGF18 mRNA and protein in the dorsal skin of mice to accelerate the HFs to enter the anagen phase earlier, thereby promoting the regeneration of hair. Thus, cucurbitacin can be considered a new and valuable agent for the development of anti-hair loss products.
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Affiliation(s)
- Keke Guo
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, China
| | - Lusheng Wang
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, China
| | - Yulan Zhong
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, China
| | - Shuang Gao
- School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Rongrong Jing
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, China
| | - Jiabin Ye
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, China
| | - Kaini Zhang
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, China
| | - Mengli Fu
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, China
| | - Zhenlin Hu
- School of Medicine, Shanghai University, Shanghai, China
| | - Wengang Zhao
- Institute of Life Sciences, Wenzhou University, Wenzhou, China
| | - Nuo Xu
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, China
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11
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Ornitz DM, Itoh N. New developments in the biology of fibroblast growth factors. WIREs Mech Dis 2022; 14:e1549. [PMID: 35142107 PMCID: PMC10115509 DOI: 10.1002/wsbm.1549] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 01/28/2023]
Abstract
The fibroblast growth factor (FGF) family is composed of 18 secreted signaling proteins consisting of canonical FGFs and endocrine FGFs that activate four receptor tyrosine kinases (FGFRs 1-4) and four intracellular proteins (intracellular FGFs or iFGFs) that primarily function to regulate the activity of voltage-gated sodium channels and other molecules. The canonical FGFs, endocrine FGFs, and iFGFs have been reviewed extensively by us and others. In this review, we briefly summarize past reviews and then focus on new developments in the FGF field since our last review in 2015. Some of the highlights in the past 6 years include the use of optogenetic tools, viral vectors, and inducible transgenes to experimentally modulate FGF signaling, the clinical use of small molecule FGFR inhibitors, an expanded understanding of endocrine FGF signaling, functions for FGF signaling in stem cell pluripotency and differentiation, roles for FGF signaling in tissue homeostasis and regeneration, a continuing elaboration of mechanisms of FGF signaling in development, and an expanding appreciation of roles for FGF signaling in neuropsychiatric diseases. This article is categorized under: Cardiovascular Diseases > Molecular and Cellular Physiology Neurological Diseases > Molecular and Cellular Physiology Congenital Diseases > Stem Cells and Development Cancer > Stem Cells and Development.
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Affiliation(s)
- David M Ornitz
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Nobuyuki Itoh
- Kyoto University Graduate School of Pharmaceutical Sciences, Sakyo, Kyoto, Japan
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12
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Kelley MW. Cochlear Development; New Tools and Approaches. Front Cell Dev Biol 2022; 10:884240. [PMID: 35813214 PMCID: PMC9260282 DOI: 10.3389/fcell.2022.884240] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 05/19/2022] [Indexed: 12/21/2022] Open
Abstract
The sensory epithelium of the mammalian cochlea, the organ of Corti, is comprised of at least seven unique cell types including two functionally distinct types of mechanosensory hair cells. All of the cell types within the organ of Corti are believed to develop from a population of precursor cells referred to as prosensory cells. Results from previous studies have begun to identify the developmental processes, lineage restrictions and signaling networks that mediate the specification of many of these cell types, however, the small size of the organ and the limited number of each cell type has hampered progress. Recent technical advances, in particular relating to the ability to capture and characterize gene expression at the single cell level, have opened new avenues for understanding cellular specification in the organ of Corti. This review will cover our current understanding of cellular specification in the cochlea, discuss the most commonly used methods for single cell RNA sequencing and describe how results from a recent study using single cell sequencing provided new insights regarding cellular specification.
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13
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Hausott B, Glueckert R, Schrott-Fischer A, Klimaschewski L. Signal Transduction Regulators in Axonal Regeneration. Cells 2022; 11:cells11091537. [PMID: 35563843 PMCID: PMC9104247 DOI: 10.3390/cells11091537] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/27/2022] [Accepted: 04/28/2022] [Indexed: 11/16/2022] Open
Abstract
Intracellular signal transduction in response to growth factor receptor activation is a fundamental process during the regeneration of the nervous system. In this context, intracellular inhibitors of neuronal growth factor signaling have become of great interest in the recent years. Among them are the prominent signal transduction regulators Sprouty (SPRY) and phosphatase and tensin homolog deleted on chromosome 10 (PTEN), which interfere with major signaling pathways such as extracellular signal-regulated kinase (ERK) or phosphoinositide 3-kinase (PI3K)/Akt in neurons and glial cells. Furthermore, SPRY and PTEN are themselves tightly regulated by ubiquitin ligases such as c-casitas b-lineage lymphoma (c-CBL) or neural precursor cell expressed developmentally down-regulated protein 4 (NEDD4) and by different microRNAs (miRs) including miR-21 and miR-222. SPRY, PTEN and their intracellular regulators play an important role in the developing and the lesioned adult central and peripheral nervous system. This review will focus on the effects of SPRY and PTEN as well as their regulators in various experimental models of axonal regeneration in vitro and in vivo. Targeting these signal transduction regulators in the nervous system holds great promise for the treatment of neurological injuries in the future.
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Affiliation(s)
- Barbara Hausott
- Institute of Neuroanatomy, Medical University Innsbruck, 6020 Innsbruck, Austria;
- Correspondence:
| | - Rudolf Glueckert
- Department of Otorhinolaryngology, Medical University Innsbruck, 6020 Innsbruck, Austria; (R.G.); (A.S.-F.)
| | - Anneliese Schrott-Fischer
- Department of Otorhinolaryngology, Medical University Innsbruck, 6020 Innsbruck, Austria; (R.G.); (A.S.-F.)
| | - Lars Klimaschewski
- Institute of Neuroanatomy, Medical University Innsbruck, 6020 Innsbruck, Austria;
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14
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Decomposing a deterministic path to mesenchymal niche formation by two intersecting morphogen gradients. Dev Cell 2022; 57:1053-1067.e5. [PMID: 35421372 PMCID: PMC9050909 DOI: 10.1016/j.devcel.2022.03.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 03/03/2022] [Accepted: 03/17/2022] [Indexed: 01/09/2023]
Abstract
Organ formation requires integrating signals to coordinate proliferation, specify cell fates, and shape tissue. Tracing these events and signals remains a challenge, as intermediate states across many critical transitions are unresolvable over real time and space. Here, we designed a unique computational approach to decompose a non-linear differentiation process into key components to resolve the signals and cell behaviors that drive a rapid transition, using the hair follicle dermal condensate as a model. Combining scRNA sequencing with genetic perturbation, we reveal that proliferative Dkk1+ progenitors transiently amplify to become quiescent dermal condensate cells by the mere spatiotemporal patterning of Wnt/β-catenin and SHH signaling gradients. Together, they deterministically coordinate a rapid transition from proliferation to quiescence, cell fate specification, and morphogenesis. Moreover, genetically repatterning these gradients reproduces these events autonomously in "slow motion" across more intermediates that resolve the process. This analysis unravels two morphogen gradients that intersect to coordinate events of organogenesis.
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15
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Jeong M, Bojkovic K, Sagi V, Stankovic KM. Molecular and Clinical Significance of Fibroblast Growth Factor 2 in Development and Regeneration of the Auditory System. Front Mol Neurosci 2022; 14:757441. [PMID: 35002617 PMCID: PMC8733209 DOI: 10.3389/fnmol.2021.757441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 11/18/2021] [Indexed: 01/25/2023] Open
Abstract
The fibroblast growth factor 2 (FGF2) is a member of the FGF family which is involved in key biological processes including development, cellular proliferation, wound healing, and angiogenesis. Although the utility of the FGF family as therapeutic agents has attracted attention, and FGF2 has been studied in several clinical contexts, there remains an incomplete understanding of the molecular and clinical function of FGF2 in the auditory system. In this review, we highlight the role of FGF2 in inner ear development and hearing protection and present relevant clinical studies for tympanic membrane (TM) repair. We conclude by discussing the future implications of FGF2 as a potential therapeutic agent.
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Affiliation(s)
- Minjin Jeong
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, United States.,Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA, United States
| | - Katarina Bojkovic
- Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA, United States
| | - Varun Sagi
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, United States.,University of Minnesota Medical School, Minneapolis, MN, United States
| | - Konstantina M Stankovic
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, United States.,Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA, United States
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16
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Riley BB. Comparative assessment of Fgf's diverse roles in inner ear development: A zebrafish perspective. Dev Dyn 2021; 250:1524-1551. [PMID: 33830554 DOI: 10.1002/dvdy.343] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/26/2021] [Accepted: 03/26/2021] [Indexed: 01/21/2023] Open
Abstract
Progress in understanding mechanisms of inner ear development has been remarkably rapid in recent years. The research community has benefited from the availability of several diverse model organisms, including zebrafish, chick, and mouse. The complexity of the inner ear has proven to be a challenge, and the complexity of the mammalian cochlea in particular has been the subject of intense scrutiny. Zebrafish lack a cochlea and exhibit a number of other differences from amniote species, hence they are sometimes seen as less relevant for inner ear studies. However, accumulating evidence shows that underlying cellular and molecular mechanisms are often highly conserved. As a case in point, consideration of the diverse functions of Fgf and its downstream effectors reveals many similarities between vertebrate species, allowing meaningful comparisons the can benefit the entire research community. In this review, I will discuss mechanisms by which Fgf controls key events in early otic development in zebrafish and provide direct comparisons with chick and mouse.
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Affiliation(s)
- Bruce B Riley
- Biology Department, Texas A&M University, College Station, Texas, USA
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17
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Kwan KY, White PM. Understanding the differentiation and epigenetics of cochlear sensory progenitors in pursuit of regeneration. Curr Opin Otolaryngol Head Neck Surg 2021; 29:366-372. [PMID: 34374667 PMCID: PMC8452321 DOI: 10.1097/moo.0000000000000741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE OF REVIEW Sensory hair cells (HCs) of the inner ear are responsible for our ability to hear and balance. Loss of these cells results in hearing loss. Stem cell replacement and in situ regeneration have the potential to replace lost HCs. Newly discovered contributions of transcription factor regulatory networks and epigenetic mechanisms in regulating HC differentiation and regeneration are placed into context of the literature. RECENT FINDINGS A wealth of new data has helped to define cochlear sensory progenitors in their developmental trajectories. This includes transcription factor networks, epigenetic manipulations, and cochlear HC subtype specification. SUMMARY Understanding how sensory progenitors differ and how HC subtypes arise will substantially inform efforts in hearing restoration.
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Affiliation(s)
- Kelvin Y. Kwan
- Department of Cell Biology & Neuroscience, Rutgers University, Piscataway, New Jersey
| | - Patricia M. White
- Department of Neuroscience, Ernest J. Del Monte Institute of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
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18
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Trela E, Lan Q, Myllymäki SM, Villeneuve C, Lindström R, Kumar V, Wickström SA, Mikkola ML. Cell influx and contractile actomyosin force drive mammary bud growth and invagination. J Cell Biol 2021; 220:e202008062. [PMID: 34042944 PMCID: PMC8164091 DOI: 10.1083/jcb.202008062] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 03/31/2021] [Accepted: 05/11/2021] [Indexed: 01/21/2023] Open
Abstract
The mammary gland develops from the surface ectoderm during embryogenesis and proceeds through morphological phases defined as placode, hillock, bud, and bulb stages followed by branching morphogenesis. During this early morphogenesis, the mammary bud undergoes an invagination process where the thickened bud initially protrudes above the surface epithelium and then transforms to a bulb and sinks into the underlying mesenchyme. The signaling pathways regulating the early morphogenetic steps have been identified to some extent, but the underlying cellular mechanisms remain ill defined. Here, we use 3D and 4D confocal microscopy to show that the early growth of the mammary rudiment is accomplished by migration-driven cell influx, with minor contributions of cell hypertrophy and proliferation. We delineate a hitherto undescribed invagination mechanism driven by thin, elongated keratinocytes-ring cells-that form a contractile rim around the mammary bud and likely exert force via the actomyosin network. Furthermore, we show that conditional deletion of nonmuscle myosin IIA (NMIIA) impairs invagination, resulting in abnormal mammary bud shape.
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MESH Headings
- Actomyosin/metabolism
- Animals
- Cell Movement
- Cell Proliferation
- Epithelial Cells/metabolism
- Epithelial Cells/ultrastructure
- Female
- Gene Expression Regulation, Developmental
- Gestational Age
- Hypertrophy
- Keratinocytes/metabolism
- Keratinocytes/ultrastructure
- Mammary Glands, Animal/embryology
- Mammary Glands, Animal/metabolism
- Mammary Glands, Animal/ultrastructure
- Mechanotransduction, Cellular
- Mice, Inbred C57BL
- Mice, Transgenic
- Microscopy, Confocal
- Microscopy, Electron, Scanning
- Microscopy, Fluorescence
- Morphogenesis
- Mice
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Affiliation(s)
- Ewelina Trela
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Qiang Lan
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Satu-Marja Myllymäki
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Clémentine Villeneuve
- Helsinki Institute of Life Science, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Riitta Lindström
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Vinod Kumar
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Sara A. Wickström
- Helsinki Institute of Life Science, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- Wihuri Research Institute, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland
- Max Planck Institute for Biology of Ageing, Cologne, Germany
- Cologne Excellence Cluster for Stress Responses in Ageing-Associated Diseases, University of Cologne, Cologne, Germany
| | - Marja L. Mikkola
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
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19
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Trivedi N, Kumar D. Fibroblast growth factor and kidney disease: Updates for emerging novel therapeutics. J Cell Physiol 2021; 236:7909-7925. [PMID: 34196395 DOI: 10.1002/jcp.30497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 05/04/2021] [Accepted: 05/28/2021] [Indexed: 01/01/2023]
Abstract
The discovery of fibroblast growth factors (FGFs) and fibroblast growth factor receptors (FGFRs) provided a profound new insight into physiological and metabolic functions. FGF has a large family by having divergent structural elements and enable functional divergence and specification. FGF and FGFRs are highly expressed during kidney development. Signals from the ureteric bud regulate morphogenesis, nephrogenesis, and nephron progenitor survival. Thus, FGF signaling plays an important role in kidney progenitor cell aggregation at the sites of new nephron formation. This review will summarize the current knowledge about functions of FGF signaling in kidney development and their ability to promote regeneration in injured kidneys and its use as a biomarker and therapeutic target in kidney diseases. Further studies are essential to determine the predictive significance of the various FGF/FGFR deviations and to integrate them into clinical algorithms.
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Affiliation(s)
- Neerja Trivedi
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Devendra Kumar
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska, USA
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20
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Mogollón I, Moustakas-Verho JE, Niittykoski M, Ahtiainen L. The initiation knot is a signaling center required for molar tooth development. Development 2021; 148:261701. [PMID: 33914869 PMCID: PMC8126415 DOI: 10.1242/dev.194597] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 03/28/2021] [Indexed: 12/03/2022]
Abstract
Signaling centers, or organizers, regulate many aspects of embryonic morphogenesis. In the mammalian molar tooth, reiterative signaling in specialized centers called enamel knots (EKs) determines tooth patterning. Preceding the primary EK, transient epithelial thickening appears, the significance of which remains debated. Using tissue confocal fluorescence imaging with laser ablation experiments, we show that this transient thickening is an earlier signaling center, the molar initiation knot (IK), that is required for the progression of tooth development. IK cell dynamics demonstrate the hallmarks of a signaling center: cell cycle exit, condensation and eventual silencing through apoptosis. IK initiation and maturation are defined by the juxtaposition of cells with high Wnt activity to Shh-expressing non-proliferating cells, the combination of which drives the growth of the tooth bud, leading to the formation of the primary EK as an independent cell cluster. Overall, the whole development of the tooth, from initiation to patterning, is driven by the iterative use of signaling centers. Summary: During tooth morphogenesis, transient thickening of the epithelium in the diastema anterior to the first developing molar is an early signaling center, the molar initiation knot (IK), which is required for the progression of mammalian molar tooth development.
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Affiliation(s)
- Isabel Mogollón
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, University of Helsinki, 00014, Finland
| | - Jacqueline E Moustakas-Verho
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, University of Helsinki, 00014, Finland.,Organismal & Evolutionary Biology Research Program, University of Helsinki, 00014, Finland
| | - Minna Niittykoski
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, University of Helsinki, 00014, Finland
| | - Laura Ahtiainen
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, University of Helsinki, 00014, Finland
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21
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Stojkovic M, Han D, Jeong M, Stojkovic P, Stankovic KM. Human induced pluripotent stem cells and CRISPR/Cas-mediated targeted genome editing: Platforms to tackle sensorineural hearing loss. STEM CELLS (DAYTON, OHIO) 2021; 39:673-696. [PMID: 33586253 DOI: 10.1002/stem.3353] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 12/13/2020] [Indexed: 11/09/2022]
Abstract
Hearing loss (HL) is a major global health problem of pandemic proportions. The most common type of HL is sensorineural hearing loss (SNHL) which typically occurs when cells within the inner ear are damaged. Human induced pluripotent stem cells (hiPSCs) can be generated from any individual including those who suffer from different types of HL. The development of new differentiation protocols to obtain cells of the inner ear including hair cells (HCs) and spiral ganglion neurons (SGNs) promises to expedite cell-based therapy and screening of potential pharmacologic and genetic therapies using human models. Considering age-related, acoustic, ototoxic, and genetic insults which are the most frequent causes of irreversible damage of HCs and SGNs, new methods of genome editing (GE), especially the CRISPR/Cas9 technology, could bring additional opportunities to understand the pathogenesis of human SNHL and identify novel therapies. However, important challenges associated with both hiPSCs and GE need to be overcome before scientific discoveries are correctly translated to effective and patient-safe applications. The purpose of the present review is (a) to summarize the findings from published reports utilizing hiPSCs for studies of SNHL, hence complementing recent reviews focused on animal studies, and (b) to outline promising future directions for deciphering SNHL using disruptive molecular and genomic technologies.
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Affiliation(s)
- Miodrag Stojkovic
- Eaton Peabody Laboratories, Department of Otolaryngology Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, USA.,Department of Otolaryngology Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, USA
| | - Dongjun Han
- Eaton Peabody Laboratories, Department of Otolaryngology Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, USA.,Department of Otolaryngology Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, USA
| | - Minjin Jeong
- Eaton Peabody Laboratories, Department of Otolaryngology Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, USA.,Department of Otolaryngology Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, USA
| | - Petra Stojkovic
- Eaton Peabody Laboratories, Department of Otolaryngology Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, USA.,Department of Otolaryngology Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, USA
| | - Konstantina M Stankovic
- Eaton Peabody Laboratories, Department of Otolaryngology Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, USA.,Department of Otolaryngology Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, USA.,Program in Speech and Hearing Bioscience and Technology, Harvard University, Cambridge, Massachusetts, USA.,Harvard Program in Therapeutic Science, Harvard Medical School, Boston, Massachusetts, USA.,Harvard Stem Cell Institute, Cambridge, Massachusetts, USA
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22
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Su Y, Yang LM, Ornitz DM. FGF20-FGFR1 signaling through MAPK and PI3K controls sensory progenitor differentiation in the organ of Corti. Dev Dyn 2021; 250:134-144. [PMID: 32735383 PMCID: PMC8415122 DOI: 10.1002/dvdy.231] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Fibroblast Growth Factor 20 (FGF20)-FGF receptor 1 (FGFR1) signaling is essential for cochlear hair cell (HC) and supporting cell (SC) differentiation. In other organ systems, FGFR1 signals through several intracellular pathways including MAPK (ERK), PI3K, phospholipase C ɣ (PLCɣ), and p38. Previous studies implicated MAPK and PI3K pathways in HC and SC development. We hypothesized that one or both would be important downstream mediators of FGF20-FGFR1 signaling for HC differentiation. RESULTS By inhibiting pathways downstream of FGFR1 in cochlea explant cultures, we established that both MAPK and PI3K pathways are required for HC differentiation while PLCɣ and p38 pathways are not. Examining the canonical PI3K pathway, we found that while AKT is necessary for HC differentiation, it is not sufficient to rescue the Fgf20-/- phenotype. To determine whether PI3K functions downstream of FGF20, we inhibited Phosphatase and Tensin Homolog (PTEN) in Fgf20-/- explants. Overactivation of PI3K resulted in a partial rescue of the Fgf20-/- phenotype, demonstrating a requirement for PI3K downstream of FGF20. Consistent with a requirement for the MAPK pathway for FGF20-regulated HC differentiation, we show that treating Fgf20-/- explants with FGF9 increased levels of dpERK. CONCLUSIONS Together, these data provide evidence that both MAPK and PI3K are important downstream mediators of FGF20-FGFR1 signaling during HC and SC differentiation.
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Affiliation(s)
- Yutao Su
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Lu M Yang
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - David M Ornitz
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
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23
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Mesenchymal ETV transcription factors regulate cochlear length. Hear Res 2020; 396:108039. [PMID: 32866767 DOI: 10.1016/j.heares.2020.108039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 05/22/2020] [Accepted: 07/02/2020] [Indexed: 11/22/2022]
Abstract
Mammalian cochlear development encompasses a series of morphological and molecular events that results in the formation of a highly intricate structure responsible for hearing. One remarkable event occurs during development is the cochlear lengthening that starts with cochlear outgrowth around E11 and continues throughout development. Different mechanisms contribute to this process including cochlear progenitor proliferation and convergent extension. We previously identified that FGF9 and FGF20 promote cochlear lengthening by regulating auditory sensory epithelial proliferation through FGFR1 and FGFR2 in the periotic mesenchyme. Here, we provide evidence that ETS-domain transcription factors ETV4 and ETV5 are downstream of mesenchymal FGF signaling to control cochlear lengthening. Next generation RNA sequencing identified that Etv1, Etv4 and Etv5 mRNAs are decreased in the Fgf9 and Fgf20 double mutant periotic mesenchyme. Deleting both Etv4 and Etv5 in periotic mesenchyme resulted in shortening of cochlear length but maintaining normal patterning of organ of Corti and density of hair cells and supporting cells. This recapitulates phenotype of mesenchymal-specific Fgfr1 and Fgfr2 deleted inner ear. Furthermore, analysis of Etv1/4/5 triple conditional mutants revealed that ETV1 does not contribute in this process. Our study reveals that ETV4 and ETV5 function downstream of mesenchymal FGF signaling to promote cochlear lengthening.
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24
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Ono K, Sandell LL, Trainor PA, Wu DK. Retinoic acid synthesis and autoregulation mediate zonal patterning of vestibular organs and inner ear morphogenesis. Development 2020; 147:dev.192070. [PMID: 32665247 DOI: 10.1242/dev.192070] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/01/2020] [Indexed: 12/13/2022]
Abstract
Retinoic acid (RA), a vitamin A (retinol) derivative, has pleiotropic functions during embryonic development. The synthesis of RA requires two enzymatic reactions: oxidation of retinol into retinaldehyde by alcohol dehydrogenases (ADHs) or retinol dehydrogenases (RDHs); and oxidation of retinaldehyde into RA by aldehyde dehydrogenases family 1, subfamily A (ALDH1as), such as ALDH1a1, ALDH1a2 and ALDH1a3. Levels of RA in tissues are regulated by spatiotemporal expression patterns of genes encoding RA-synthesizing and -degrading enzymes, such as cytochrome P450 26 (Cyp26 genes). Here, we show that RDH10 is important for both sensory and non-sensory formation of the vestibule of the inner ear. Mice deficient in Rdh10 exhibit failure of utricle-saccule separation, otoconial formation and zonal patterning of vestibular sensory organs. These phenotypes are similar to those of Aldh1a3 knockouts, and the sensory phenotype is complementary to that of Cyp26b1 knockouts. Together, these results demonstrate that RDH10 and ALDH1a3 are the key RA-synthesis enzymes involved in vestibular development. Furthermore, we discovered that RA induces Cyp26b1 expression in the developing vestibular sensory organs, which generates the differential RA signaling required for zonal patterning.
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Affiliation(s)
- Kazuya Ono
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lisa L Sandell
- Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY 40201, USA
| | - Paul A Trainor
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA.,Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Doris K Wu
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
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25
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Huh SH, Ha L, Jang HS. Nephron Progenitor Maintenance Is Controlled through Fibroblast Growth Factors and Sprouty1 Interaction. J Am Soc Nephrol 2020; 31:2559-2572. [PMID: 32753399 DOI: 10.1681/asn.2020040401] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 07/08/2020] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Nephron progenitor cells (NPCs) give rise to all segments of functional nephrons and are of great interest due to their potential as a source for novel treatment strategies for kidney disease. Fibroblast growth factor (FGF) signaling plays pivotal roles in generating and maintaining NPCs during kidney development, but little is known about the molecule(s) regulating FGF signaling during nephron development. Sprouty 1 (SPRY1) is an antagonist of receptor tyrosine kinases. Although SPRY1 antagonizes Ret-GDNF signaling, which modulates renal branching, its role in NPCs is not known. METHODS Spry1, Fgf9, and Fgf20 compound mutant animals were used to evaluate kidney phenotypes in mice to understand whether SPRY1 modulates FGF signaling in NPCs and whether FGF8 functions with FGF9 and FGF20 in maintaining NPCs. RESULTS Loss of one copy of Spry1 counters effects of the loss of Fgf9 and Fgf20, rescuing bilateral renal agenesis premature NPC differentiation, NPC proliferation, and cell death defects. In the absence of SPRY1, FGF9, and FGF20, another FGF ligand, FGF8, promotes nephrogenesis. Deleting both Fgf8 and Fgf20 results in kidney agenesis, defects in NPC proliferation, and cell death. Deleting one copy of Fgf8 reversed the effect of deleting one copy of Spry1, which rescued the renal agenesis due to loss of Fgf9 and Fgf20. CONCLUSIONS SPRY1 expressed in NPCs modulates the activity of FGF signaling and regulates NPC stemness. These findings indicate the importance of the balance between positive and negative signals during NPC maintenance.
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Affiliation(s)
- Sung-Ho Huh
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, Nebraska .,Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, Nebraska
| | - Ligyeom Ha
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, Nebraska
| | - Hee-Seong Jang
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska
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26
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Yang LM, Stout L, Rauchman M, Ornitz DM. Analysis of FGF20-regulated genes in organ of Corti progenitors by translating ribosome affinity purification. Dev Dyn 2020; 249:1217-1242. [PMID: 32492250 DOI: 10.1002/dvdy.211] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/26/2020] [Accepted: 05/27/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Understanding the mechanisms that regulate hair cell (HC) differentiation in the organ of Corti (OC) is essential to designing genetic therapies for hearing loss due to HC loss or damage. We have previously identified Fibroblast Growth Factor 20 (FGF20) as having a key role in HC and supporting cell differentiation in the mouse OC. To investigate the genetic landscape regulated by FGF20 signaling in OC progenitors, we employ Translating Ribosome Affinity Purification combined with Next Generation RNA Sequencing (TRAPseq) in the Fgf20 lineage. RESULTS We show that TRAPseq targeting OC progenitors effectively enriched for RNA from this rare cell population. TRAPseq identified differentially expressed genes (DEGs) downstream of FGF20, including Etv4, Etv5, Etv1, Dusp6, Hey1, Hey2, Heyl, Tectb, Fat3, Cpxm2, Sall1, Sall3, and cell cycle regulators such as Cdc20. Analysis of Cdc20 conditional-null mice identified decreased cochlea length, while analysis of Sall1-null and Sall1-ΔZn2-10 mice, which harbor a mutation that causes Townes-Brocks syndrome, identified a decrease in outer hair cell number. CONCLUSIONS We present two datasets: genes with enriched expression in OC progenitors, and DEGs downstream of FGF20 in the embryonic day 14.5 cochlea. We validate select DEGs via in situ hybridization and in vivo functional studies in mice.
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Affiliation(s)
- Lu M Yang
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Lisa Stout
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Michael Rauchman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - David M Ornitz
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
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27
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Kolla L, Kelly MC, Mann ZF, Anaya-Rocha A, Ellis K, Lemons A, Palermo AT, So KS, Mays JC, Orvis J, Burns JC, Hertzano R, Driver EC, Kelley MW. Characterization of the development of the mouse cochlear epithelium at the single cell level. Nat Commun 2020; 11:2389. [PMID: 32404924 PMCID: PMC7221106 DOI: 10.1038/s41467-020-16113-y] [Citation(s) in RCA: 158] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 04/10/2020] [Indexed: 12/14/2022] Open
Abstract
Mammalian hearing requires the development of the organ of Corti, a sensory epithelium comprising unique cell types. The limited number of each of these cell types, combined with their close proximity, has prevented characterization of individual cell types and/or their developmental progression. To examine cochlear development more closely, we transcriptionally profile approximately 30,000 isolated mouse cochlear cells collected at four developmental time points. Here we report on the analysis of those cells including the identification of both known and unknown cell types. Trajectory analysis for OHCs indicates four phases of gene expression while fate mapping of progenitor cells suggests that OHCs and their surrounding supporting cells arise from a distinct (lateral) progenitor pool. Tgfβr1 is identified as being expressed in lateral progenitor cells and a Tgfβr1 antagonist inhibits OHC development. These results provide insights regarding cochlear development and demonstrate the potential value and application of this data set. How the development of the cochlear epithelium is regulated is unclear. Here, the authors use single cell RNAseq analysis to provide insight into the transcriptional changes arising during development of the murine cochlear inner and outer hair cells.
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Affiliation(s)
- Likhitha Kolla
- Laboratory of Cochlear Development, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Michael C Kelly
- Laboratory of Cochlear Development, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Zoe F Mann
- Centre for Craniofacial and Regenerative Biology, King's College London, London, UK
| | - Alejandro Anaya-Rocha
- Laboratory of Cochlear Development, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Kathryn Ellis
- Laboratory of Cochlear Development, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Abigail Lemons
- Laboratory of Cochlear Development, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Adam T Palermo
- Decibel Therapeutics, 1325 Boylston, Str., Suite 500, Boston, MA, 02215, USA
| | - Kathy S So
- Decibel Therapeutics, 1325 Boylston, Str., Suite 500, Boston, MA, 02215, USA
| | - Joseph C Mays
- Laboratory of Cochlear Development, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Joshua Orvis
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Joseph C Burns
- Decibel Therapeutics, 1325 Boylston, Str., Suite 500, Boston, MA, 02215, USA
| | - Ronna Hertzano
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.,Department of Otorhinolaryngology Head and Neck Surgery, Anatomy and Neurobiology, and Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Elizabeth C Driver
- Laboratory of Cochlear Development, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Matthew W Kelley
- Laboratory of Cochlear Development, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA.
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β-Catenin is required for radial cell patterning and identity in the developing mouse cochlea. Proc Natl Acad Sci U S A 2019; 116:21054-21060. [PMID: 31570588 DOI: 10.1073/pnas.1910223116] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Development of multicellular organs requires the coordination of cell differentiation and patterning. Critical for sound detection, the mammalian organ of Corti contains functional units arranged tonotopically along the cochlear turns. Each unit consists of sensory hair cells intercalated by nonsensory supporting cells, both specified and radially patterned with exquisite precision during embryonic development. However, how cell identity and radial patterning are jointly controlled is poorly understood. Here we show that β-catenin is required for specification of hair cell and supporting cell subtypes and radial patterning of the cochlea in vivo. In 2 mouse models of conditional β-catenin deletion, early specification of Myosin7-expressing hair cells and Prox1-positive supporting cells was preserved. While β-catenin-deficient cochleae expressed FGF8 and FGFR3, both of which are essential for pillar cell specification, the radial patterning of organ of Corti was disrupted, revealed by aberrant expression of cadherins and the pillar cell markers P75 and Lgr6. Moreover, β-catenin ablation caused duplication of FGF8-positive inner hair cells and reduction of outer hair cells without affecting the overall hair cell density. In contrast, in another transgenic model with suppressed transcriptional activity of β-catenin but preserved cell adhesion function, both specification and radial patterning of the organ of Corti were intact. Our study reveals specific functions of β-catenin in governing cell identity and patterning mediated through cell adhesion in the developing cochlea.
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Yang LM, Cheah KSE, Huh SH, Ornitz DM. Sox2 and FGF20 interact to regulate organ of Corti hair cell and supporting cell development in a spatially-graded manner. PLoS Genet 2019; 15:e1008254. [PMID: 31276493 PMCID: PMC6636783 DOI: 10.1371/journal.pgen.1008254] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 07/17/2019] [Accepted: 06/18/2019] [Indexed: 01/24/2023] Open
Abstract
The mouse organ of Corti, housed inside the cochlea, contains hair cells and supporting cells that transduce sound into electrical signals. These cells develop in two main steps: progenitor specification followed by differentiation. Fibroblast Growth Factor (FGF) signaling is important in this developmental pathway, as deletion of FGF receptor 1 (Fgfr1) or its ligand, Fgf20, leads to the loss of hair cells and supporting cells from the organ of Corti. However, whether FGF20-FGFR1 signaling is required during specification or differentiation, and how it interacts with the transcription factor Sox2, also important for hair cell and supporting cell development, has been a topic of debate. Here, we show that while FGF20-FGFR1 signaling functions during progenitor differentiation, FGFR1 has an FGF20-independent, Sox2-dependent role in specification. We also show that a combination of reduction in Sox2 expression and Fgf20 deletion recapitulates the Fgfr1-deletion phenotype. Furthermore, we uncovered a strong genetic interaction between Sox2 and Fgf20, especially in regulating the development of hair cells and supporting cells towards the basal end and the outer compartment of the cochlea. To explain this genetic interaction and its effects on the basal end of the cochlea, we provide evidence that decreased Sox2 expression delays specification, which begins at the apex of the cochlea and progresses towards the base, while Fgf20-deletion results in premature onset of differentiation, which begins near the base of the cochlea and progresses towards the apex. Thereby, Sox2 and Fgf20 interact to ensure that specification occurs before differentiation towards the cochlear base. These findings reveal an intricate developmental program regulating organ of Corti development along the basal-apical axis of the cochlea.
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Affiliation(s)
- Lu M. Yang
- Department of Developmental Biology; Washington University School of Medicine; St. Louis, Missouri, United States of America
| | - Kathryn S. E. Cheah
- School of Biomedical Sciences; The University of Hong Kong; Pokfulam, Hong Kong, China
| | - Sung-Ho Huh
- Department of Developmental Biology; Washington University School of Medicine; St. Louis, Missouri, United States of America
- Holland Regenerative Medicine Program, and the Department of Neurological Sciences; University of Nebraska Medical Center; Omaha, Nebraska, United States of America
- * E-mail: (DMO); (SH)
| | - David M. Ornitz
- Department of Developmental Biology; Washington University School of Medicine; St. Louis, Missouri, United States of America
- * E-mail: (DMO); (SH)
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30
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Par3 is essential for the establishment of planar cell polarity of inner ear hair cells. Proc Natl Acad Sci U S A 2019; 116:4999-5008. [PMID: 30814219 DOI: 10.1073/pnas.1816333116] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In the inner ear sensory epithelia, stereociliary hair bundles atop sensory hair cells are mechanosensory apparatus with planar polarized structure and orientation. This is established during development by the concerted action of tissue-level, intercellular planar cell polarity (PCP) signaling and a hair cell-intrinsic, microtubule-mediated machinery. However, how various polarity signals are integrated during hair bundle morphogenesis is poorly understood. Here, we show that the conserved cell polarity protein Par3 is essential for planar polarization of hair cells. Par3 deletion in the inner ear disrupted cochlear outgrowth, hair bundle orientation, kinocilium positioning, and basal body planar polarity, accompanied by defects in the organization and cortical attachment of hair cell microtubules. Genetic mosaic analysis revealed that Par3 functions both cell-autonomously and cell-nonautonomously to regulate kinocilium positioning and hair bundle orientation. At the tissue level, intercellular PCP signaling regulates the asymmetric localization of Par3, which in turn maintains the asymmetric localization of the core PCP protein Vangl2. Mechanistically, Par3 interacts with and regulates the localization of Tiam1 and Trio, which are guanine nucleotide exchange factors (GEFs) for Rac, thereby stimulating Rac-Pak signaling. Finally, constitutively active Rac1 rescued the PCP defects in Par3-deficient cochleae. Thus, a Par3-GEF-Rac axis mediates both tissue-level and hair cell-intrinsic PCP signaling.
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31
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Mok KW, Saxena N, Heitman N, Grisanti L, Srivastava D, Muraro MJ, Jacob T, Sennett R, Wang Z, Su Y, Yang LM, Ma'ayan A, Ornitz DM, Kasper M, Rendl M. Dermal Condensate Niche Fate Specification Occurs Prior to Formation and Is Placode Progenitor Dependent. Dev Cell 2019; 48:32-48.e5. [PMID: 30595537 PMCID: PMC6370312 DOI: 10.1016/j.devcel.2018.11.034] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 10/31/2018] [Accepted: 11/27/2018] [Indexed: 12/29/2022]
Abstract
Cell fate transitions are essential for specification of stem cells and their niches, but the precise timing and sequence of molecular events during embryonic development are largely unknown. Here, we identify, with 3D and 4D microscopy, unclustered precursors of dermal condensates (DC), signaling niches for epithelial progenitors in hair placodes. With population-based and single-cell transcriptomics, we define a molecular time-lapse from pre-DC fate specification through DC niche formation and establish the developmental trajectory as the DC lineage emerges from fibroblasts. Co-expression of downregulated fibroblast and upregulated DC genes in niche precursors reveals a transitory molecular state following a proliferation shutdown. Waves of transcription factor and signaling molecule expression then coincide with DC formation. Finally, ablation of epidermal Wnt signaling and placode-derived FGF20 demonstrates their requirement for pre-DC specification. These findings uncover a progenitor-dependent niche precursor fate and the transitory molecular events controlling niche formation and function.
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Affiliation(s)
- Ka-Wai Mok
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA
| | - Nivedita Saxena
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA
| | - Nicholas Heitman
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA
| | - Laura Grisanti
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA
| | - Devika Srivastava
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA
| | - Mauro J Muraro
- Oncode Institute, Hubrecht Institute-KNAW (Royal Netherlands Academy of Arts and Sciences), and University Medical Center Utrecht, Utrecht 3584 CT, the Netherlands
| | - Tina Jacob
- Department of Biosciences and Nutrition and Center for Innovative Medicine, Karolinska Institutet, Huddinge 141 83, Sweden
| | - Rachel Sennett
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA
| | - Zichen Wang
- Department of Pharmacological Sciences, Mount Sinai Center for Bioinformatics, BD2K-LINCS Data Coordination and Integration Center, Knowledge Management Center for Illuminating the Druggable Genome (KMC-IDG), Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yutao Su
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Lu M Yang
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Avi Ma'ayan
- Department of Pharmacological Sciences, Mount Sinai Center for Bioinformatics, BD2K-LINCS Data Coordination and Integration Center, Knowledge Management Center for Illuminating the Druggable Genome (KMC-IDG), Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - David M Ornitz
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Maria Kasper
- Department of Biosciences and Nutrition and Center for Innovative Medicine, Karolinska Institutet, Huddinge 141 83, Sweden
| | - Michael Rendl
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA; Department of Dermatology, Icahn School of Medicine at Mount Sinai, Atran Building AB7-10C, Box 1020, New York, NY 10029, USA.
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32
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Yang LM, Huh SH, Ornitz DM. FGF20-Expressing, Wnt-Responsive Olfactory Epithelial Progenitors Regulate Underlying Turbinate Growth to Optimize Surface Area. Dev Cell 2018; 46:564-580.e5. [PMID: 30100263 DOI: 10.1016/j.devcel.2018.07.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 05/09/2018] [Accepted: 07/11/2018] [Indexed: 01/06/2023]
Abstract
The olfactory epithelium (OE) is a neurosensory organ required for the sense of smell. Turbinates, bony projections from the nasal cavity wall, increase the surface area within the nasal cavity lined by the OE. Here, we use engineered fibroblast growth factor 20 (Fgf20) knockin alleles to identify a population of OE progenitor cells that expand horizontally during development to populate all lineages of the mature OE. We show that these Fgf20-positive epithelium-spanning progenitor (FEP) cells are responsive to Wnt/β-Catenin signaling. Wnt signaling suppresses FEP cell differentiation into OE basal progenitors and their progeny and positively regulates Fgf20 expression. We further show that FGF20 signals to the underlying mesenchyme to regulate the growth of turbinates. These studies thus identify a population of OE progenitor cells that function to scale OE surface area with the underlying turbinates.
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Affiliation(s)
- Lu M Yang
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Sung-Ho Huh
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - David M Ornitz
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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33
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FGF signalling controls the specification of hair placode-derived SOX9 positive progenitors to Merkel cells. Nat Commun 2018; 9:2333. [PMID: 29899403 PMCID: PMC5998134 DOI: 10.1038/s41467-018-04399-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 04/27/2018] [Indexed: 12/14/2022] Open
Abstract
Merkel cells are innervated mechanosensory cells responsible for light-touch sensations. In murine dorsal skin, Merkel cells are located in touch domes and found in the epidermis around primary hairs. While it has been shown that Merkel cells are skin epithelial cells, the progenitor cell population that gives rise to these cells is unknown. Here, we show that during embryogenesis, SOX9-positive (+) cells inside hair follicles, which were previously known to give rise to hair follicle stem cells (HFSCs) and cells of the hair follicle lineage, can also give rise to Merkel Cells. Interestingly, while SOX9 is critical for HFSC specification, it is dispensable for Merkel cell formation. Conversely, FGFR2 is required for Merkel cell formation but is dispensable for HFSCs. Together, our studies uncover SOX9(+) cells as precursors of Merkel cells and show the requirement for FGFR2-mediated epithelial signalling in Merkel cell specification. Merkel cells are mechanoreceptors located in the epidermis whose developmental origin is unclear. Here the authors show that Merkel cells originate from SOX9 positive cells inside hair follicles and that FGFR2-mediated epithelial signalling is required for their specification.
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34
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Spatiotemporal coordination of cellular differentiation and tissue morphogenesis in organ of Corti development. Med Mol Morphol 2018. [PMID: 29536272 DOI: 10.1007/s00795-018-0185-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The organ of Corti, an acoustic sensory organ, is a specifically differentiated epithelium of the cochlear duct, which is a part of the membranous labyrinth in the inner ear. Cells in the organ of Corti are generally classified into two kinds; hair cells, which transduce the mechanical stimuli of sound to the cell membrane electrical potential differences, and supporting cells. These cells emerge from homogeneous prosensory epithelium through cell fate determination and differentiation. In the organ of Corti organogenesis, cell differentiation and the rearrangement of their position proceed in parallel, resulting in a characteristic alignment of mature hair cells and supporting cells. Recently, studies have focused on the signaling molecules and transcription factors that regulate cell fate determination and differentiation processes. In comparison, less is known about the mechanism of the formation of the tissue architecture; however, this is important in the morphogenesis of the organ of Corti. Thus, this review will introduce previous findings that focus on how cell fate determination, cell differentiation, and whole tissue morphogenesis proceed in a spatiotemporally and finely coordinated manner. This overview provides an insight into the regulatory mechanisms of the coordination in the developing organ of Corti.
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35
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Combes AN, Wilson S, Phipson B, Binnie BB, Ju A, Lawlor KT, Cebrian C, Walton SL, Smyth IM, Moritz KM, Kopan R, Oshlack A, Little MH. Haploinsufficiency for the Six2 gene increases nephron progenitor proliferation promoting branching and nephron number. Kidney Int 2017; 93:589-598. [PMID: 29217079 DOI: 10.1016/j.kint.2017.09.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 09/03/2017] [Accepted: 09/07/2017] [Indexed: 01/05/2023]
Abstract
The regulation of final nephron number in the kidney is poorly understood. Cessation of nephron formation occurs when the self-renewing nephron progenitor population commits to differentiation. Transcription factors within this progenitor population, such as SIX2, are assumed to control expression of genes promoting self-renewal such that homozygous Six2 deletion results in premature commitment and an early halt to kidney development. In contrast, Six2 heterozygotes were assumed to be unaffected. Using quantitative morphometry, we found a paradoxical 18% increase in ureteric branching and final nephron number in Six2 heterozygotes, despite evidence for reduced levels of SIX2 protein and transcript. This was accompanied by a clear shift in nephron progenitor identity with a distinct subset of downregulated progenitor genes such as Cited1 and Meox1 while other genes were unaffected. The net result was an increase in nephron progenitor proliferation, as assessed by elevated EdU (5-ethynyl-2'-deoxyuridine) labeling, an increase in MYC protein, and transcriptional upregulation of MYC target genes. Heterozygosity for Six2 on an Fgf20-/- background resulted in premature differentiation of the progenitor population, confirming that progenitor regulation is compromised in Six2 heterozygotes. Overall, our studies reveal a unique dose response of nephron progenitors to the level of SIX2 protein in which the role of SIX2 in progenitor proliferation versus self-renewal is separable.
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Affiliation(s)
- Alexander N Combes
- Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia; Murdoch Children's Research Institute, Parkville, Victoria, Australia.
| | - Sean Wilson
- Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - Belinda Phipson
- Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - Brandon B Binnie
- Division of Cell Biology and Molecular Medicine, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Adler Ju
- Division of Cell Biology and Molecular Medicine, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Kynan T Lawlor
- Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - Cristina Cebrian
- Division of Gastroenterology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Sarah L Walton
- School of Biomedical Sciences and Centre for Children's Health Research, The University of Queensland, Brisbane, Queensland, Australia
| | - Ian M Smyth
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Australia; Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia; Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Karen M Moritz
- School of Biomedical Sciences and Centre for Children's Health Research, The University of Queensland, Brisbane, Queensland, Australia
| | - Raphael Kopan
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Alicia Oshlack
- Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - Melissa H Little
- Murdoch Children's Research Institute, Parkville, Victoria, Australia; Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia.
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36
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Notch and Fgf signaling during electrosensory versus mechanosensory lateral line organ development in a non-teleost ray-finned fish. Dev Biol 2017; 431:48-58. [PMID: 28818669 PMCID: PMC5650464 DOI: 10.1016/j.ydbio.2017.08.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 06/05/2017] [Accepted: 08/11/2017] [Indexed: 02/07/2023]
Abstract
The lateral line system is a useful model for studying the embryonic and evolutionary diversification of different organs and cell types. In jawed vertebrates, this ancestrally comprises lines of mechanosensory neuromasts over the head and trunk, flanked on the head by fields of electrosensory ampullary organs, all innervated by lateral line neurons in cranial lateral line ganglia. Both types of sense organs, and their afferent neurons, develop from cranial lateral line placodes. Current research primarily focuses on the posterior lateral line primordium in zebrafish, which migrates as a cell collective along the trunk; epithelial rosettes form in the trailing zone and are deposited as a line of neuromasts, within which hair cells and supporting cells differentiate. However, in at least some other teleosts (e.g. catfishes) and all non-teleosts, lines of cranial neuromasts are formed by placodes that elongate to form a sensory ridge, which subsequently fragments, with neuromasts differentiating in a line along the crest of the ridge. Furthermore, in many non-teleost species, electrosensory ampullary organs develop from the flanks of the sensory ridge. It is unknown to what extent the molecular mechanisms underlying neuromast formation from the zebrafish migrating posterior lateral line primordium are conserved with the as-yet unexplored molecular mechanisms underlying neuromast and ampullary organ formation from elongating lateral line placodes. Here, we report experiments in an electroreceptive non-teleost ray-finned fish, the Mississippi paddlefish Polyodon spathula, that suggest a conserved role for Notch signaling in regulating lateral line organ receptor cell number, but potentially divergent roles for the fibroblast growth factor signaling pathway, both between neuromasts and ampullary organs, and between paddlefish and zebrafish. Notch and Fgf pathway genes are expressed during paddlefish lateral line development. Fgf ligand genes are differentially expressed in neuromasts and ampullary organs. DAPT treatment results in irregular organ spacing and supernumerary receptor cells. SU5402 treatment yields fewer neuromasts, but ampullary organs form precociously. SU5402 treatment also results in supernumerary receptor cells.
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37
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Abstract
Mammalian inner ear comprises of six sensory organs; cochlea, utricle, saccule, and three semicircular canals. The cochlea contains sensory epithelium known as the organ of Corti which senses sound through mechanosensory hair cells. Mammalian inner ear undergoes series of morphogenesis during development beginning thickening of ectoderm nearby hindbrain. These events require tight regulation of multiple signaling cascades including FGF, Wnt, Notch and Bmp signaling. In this review, we will discuss the role of newly emerging signaling, FGF signaling, for its roles required for cochlear development. [BMB Reports 2017; 50(10): 487-495].
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Affiliation(s)
- Michael Ebeid
- Department of Developmental Neuroscience, Munroe Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska,
USA
| | - Sung-Ho Huh
- Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, Nebraska,
USA
- Department of Developmental Neuroscience, Munroe Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska,
USA
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38
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Ectodysplasin target gene Fgf20 regulates mammary bud growth and ductal invasion and branching during puberty. Sci Rep 2017; 7:5049. [PMID: 28698625 PMCID: PMC5505952 DOI: 10.1038/s41598-017-04637-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 05/18/2017] [Indexed: 11/18/2022] Open
Abstract
Mammary gland development begins with the appearance of epithelial placodes that invaginate, sprout, and branch to form small arborized trees by birth. The second phase of ductal growth and branching is driven by the highly invasive structures called terminal end buds (TEBs) that form at ductal tips at the onset of puberty. Ectodysplasin (Eda), a tumor necrosis factor-like ligand, is essential for the development of skin appendages including the breast. In mice, Eda regulates mammary placode formation and branching morphogenesis, but the underlying molecular mechanisms are poorly understood. Fibroblast growth factor (Fgf) receptors have a recognized role in mammary ductal development and stem cell maintenance, but the ligands involved are ill-defined. Here we report that Fgf20 is expressed in embryonic mammary glands and is regulated by the Eda pathway. Fgf20 deficiency does not impede mammary gland induction, but compromises mammary bud growth, as well as TEB formation, ductal outgrowth and branching during puberty. We further show that loss of Fgf20 delays formation of Eda-induced supernumerary mammary buds and normalizes the embryonic and postnatal hyperbranching phenotype of Eda overexpressing mice. These findings identify a hitherto unknown function for Fgf20 in mammary budding and branching morphogenesis.
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39
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Chen Q, Quan Y, Wang N, Xie C, Ji Z, He H, Chai R, Li H, Yin S, Chin YE, Wei X, Gao WQ. Inactivation of STAT3 Signaling Impairs Hair Cell Differentiation in the Developing Mouse Cochlea. Stem Cell Reports 2017; 9:231-246. [PMID: 28669599 PMCID: PMC5511372 DOI: 10.1016/j.stemcr.2017.05.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Revised: 05/24/2017] [Accepted: 05/24/2017] [Indexed: 11/19/2022] Open
Abstract
Although STAT3 signaling is demonstrated to regulate sensory cell differentiation and regeneration in the zebrafish, its exact role is still unclear in mammalian cochleae. Here, we report that STAT3 and its activated form are specifically expressed in hair cells during mouse cochlear development. Importantly, conditional cochlear deletion of Stat3 leads to an inhibition on hair cell differentiation in mice in vivo and in vitro. By cell fate analysis, inactivation of STAT3 signaling shifts the cell division modes from asymmetric to symmetric divisions from supporting cells. Moreover, inhibition of Notch signaling stimulates STAT3 phosphorylation, and inactivation of STAT3 signaling attenuates production of supernumerary hair cells induced by a Notch pathway inhibitor. Our findings highlight an important role of the STAT3 signaling during mouse cochlear hair cell differentiation and may have clinical implications for the recovery of hair cell loss-induced hearing impairment.
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Affiliation(s)
- Qianqian Chen
- State Key Laboratory of Oncogenes and Related Genes, Renji-MedX Stem Cell Research Center, Ren Ji Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China; Med-X Research Institute & School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Yizhou Quan
- State Key Laboratory of Oncogenes and Related Genes, Renji-MedX Stem Cell Research Center, Ren Ji Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China; Med-X Research Institute & School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Naitao Wang
- State Key Laboratory of Oncogenes and Related Genes, Renji-MedX Stem Cell Research Center, Ren Ji Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Chengying Xie
- Med-X Research Institute & School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Zhongzhong Ji
- State Key Laboratory of Oncogenes and Related Genes, Renji-MedX Stem Cell Research Center, Ren Ji Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China; Med-X Research Institute & School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Hao He
- Med-X Research Institute & School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China; The Affiliated Six People's Hospital, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Renjie Chai
- MOE Key Laboratory of Developmental Genes and Human Disease, Institute of Life Sciences, Southeast University, Nanjing 210096, China
| | - Huawei Li
- Otorhinolaryngology Department of Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200031, China
| | - Shankai Yin
- The Affiliated Six People's Hospital, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Y Eugene Chin
- China Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences-Shanghai Jiao Tong University School of Medicine, Shanghai 200031, China
| | - Xunbin Wei
- State Key Laboratory of Oncogenes and Related Genes, Renji-MedX Stem Cell Research Center, Ren Ji Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China; Med-X Research Institute & School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China.
| | - Wei-Qiang Gao
- State Key Laboratory of Oncogenes and Related Genes, Renji-MedX Stem Cell Research Center, Ren Ji Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China; Med-X Research Institute & School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China; The Affiliated Six People's Hospital, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China.
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40
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Ahtiainen L, Uski I, Thesleff I, Mikkola ML. Early epithelial signaling center governs tooth budding morphogenesis. J Cell Biol 2017; 214:753-67. [PMID: 27621364 PMCID: PMC5021093 DOI: 10.1083/jcb.201512074] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 08/17/2016] [Indexed: 12/22/2022] Open
Abstract
During organogenesis, cell fate specification and patterning are regulated by signaling centers, specialized clusters of morphogen-expressing cells. In many organs, initiation of development is marked by bud formation, but the cellular mechanisms involved are ill defined. Here, we use the mouse incisor tooth as a model to study budding morphogenesis. We show that a group of nonproliferative epithelial cells emerges in the early tooth primordium and identify these cells as a signaling center. Confocal live imaging of tissue explants revealed that although these cells reorganize dynamically, they do not reenter the cell cycle or contribute to the growing tooth bud. Instead, budding is driven by proliferation of the neighboring cells. We demonstrate that the activity of the ectodysplasin/Edar/nuclear factor κB pathway is restricted to the signaling center, and its inactivation leads to fewer quiescent cells and a smaller bud. These data functionally link the signaling center size to organ size and imply that the early signaling center is a prerequisite for budding morphogenesis.
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Affiliation(s)
- Laura Ahtiainen
- Developmental Biology Program, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Isa Uski
- Developmental Biology Program, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Irma Thesleff
- Developmental Biology Program, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Marja L Mikkola
- Developmental Biology Program, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
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41
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Basch ML, Brown RM, Jen HI, Semerci F, Depreux F, Edlund RK, Zhang H, Norton CR, Gridley T, Cole SE, Doetzlhofer A, Maletic-Savatic M, Segil N, Groves AK. Fine-tuning of Notch signaling sets the boundary of the organ of Corti and establishes sensory cell fates. eLife 2016; 5:19921. [PMID: 27966429 PMCID: PMC5215100 DOI: 10.7554/elife.19921] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 12/12/2016] [Indexed: 01/08/2023] Open
Abstract
The signals that induce the organ of Corti and define its boundaries in the cochlea are poorly understood. We show that two Notch modifiers, Lfng and Mfng, are transiently expressed precisely at the neural boundary of the organ of Corti. Cre-Lox fate mapping shows this region gives rise to inner hair cells and their associated inner phalangeal cells. Mutation of Lfng and Mfng disrupts this boundary, producing unexpected duplications of inner hair cells and inner phalangeal cells. This phenotype is mimicked by other mouse mutants or pharmacological treatments that lower but not abolish Notch signaling. However, strong disruption of Notch signaling causes a very different result, generating many ectopic hair cells at the expense of inner phalangeal cells. Our results show that Notch signaling is finely calibrated in the cochlea to produce precisely tuned levels of signaling that first set the boundary of the organ of Corti and later regulate hair cell development. DOI:http://dx.doi.org/10.7554/eLife.19921.001
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Affiliation(s)
- Martin L Basch
- Department of Neuroscience, Baylor College of Medicine, Houston, United States
| | - Rogers M Brown
- Program in Developmental Biology, Baylor College of Medicine, Houston, United States
| | - Hsin-I Jen
- Program in Developmental Biology, Baylor College of Medicine, Houston, United States
| | - Fatih Semerci
- Program in Developmental Biology, Baylor College of Medicine, Houston, United States
| | - Frederic Depreux
- Department of Cell Biology and Anatomy, Rosalind Franklin University of Medicine and Science, Chicago, United States
| | - Renée K Edlund
- Program in Developmental Biology, Baylor College of Medicine, Houston, United States
| | - Hongyuan Zhang
- Department of Neuroscience, Baylor College of Medicine, Houston, United States
| | | | - Thomas Gridley
- Maine Medical Center Research Institute, Scarborough, United States
| | - Susan E Cole
- Department of Molecular Genetics, The Ohio State University, Columbus, United States
| | - Angelika Doetzlhofer
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University, School of Medicine, Baltimore, United States
| | - Mirjana Maletic-Savatic
- Department of Neuroscience, Baylor College of Medicine, Houston, United States.,Program in Developmental Biology, Baylor College of Medicine, Houston, United States.,Department of Pediatrics, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, United States
| | - Neil Segil
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, United States
| | - Andrew K Groves
- Department of Neuroscience, Baylor College of Medicine, Houston, United States.,Program in Developmental Biology, Baylor College of Medicine, Houston, United States.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States
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42
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Abstract
The fibroblast growth factor (Fgf) family of ligands and receptor tyrosine kinases is required throughout embryonic and postnatal development and also regulates multiple homeostatic functions in the adult. Here, Brewer et al. review the mechanisms of Fgf signaling by focusing on genetic strategies that enable in vivo analysis. The fibroblast growth factor (Fgf) family of ligands and receptor tyrosine kinases is required throughout embryonic and postnatal development and also regulates multiple homeostatic functions in the adult. Aberrant Fgf signaling causes many congenital disorders and underlies multiple forms of cancer. Understanding the mechanisms that govern Fgf signaling is therefore important to appreciate many aspects of Fgf biology and disease. Here we review the mechanisms of Fgf signaling by focusing on genetic strategies that enable in vivo analysis. These studies support an important role for Erk1/2 as a mediator of Fgf signaling in many biological processes but have also provided strong evidence for additional signaling pathways in transmitting Fgf signaling in vivo.
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Affiliation(s)
- J Richard Brewer
- Department of Developmental and Regenerative Biology, Tisch Cancer Institute, Icahn School of Medicine at Mt. Sinai, New York, New York 10029, USA
| | - Pierre Mazot
- Department of Developmental and Regenerative Biology, Tisch Cancer Institute, Icahn School of Medicine at Mt. Sinai, New York, New York 10029, USA
| | - Philippe Soriano
- Department of Developmental and Regenerative Biology, Tisch Cancer Institute, Icahn School of Medicine at Mt. Sinai, New York, New York 10029, USA
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43
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Abstract
UNLABELLED Mechanosensory hair cells (HCs) residing in the inner ear are critical for hearing and balance. Precise coordination of proliferation, sensory specification, and differentiation during development is essential to ensure the correct patterning of HCs in the cochlear and vestibular epithelium. Recent studies have revealed that FGF20 signaling is vital for proper HC differentiation. However, the mechanisms by which FGF20 signaling promotes HC differentiation remain unknown. Here, we show that mitogen-activated protein 3 kinase 4 (MEKK4) expression is highly regulated during inner ear development and is critical to normal cytoarchitecture and function. Mice homozygous for a kinase-inactive MEKK4 mutation exhibit significant hearing loss. Lack of MEKK4 activity in vivo also leads to a significant reduction in the number of cochlear and vestibular HCs, suggesting that MEKK4 activity is essential for overall development of HCs within the inner ear. Furthermore, we show that loss of FGF20 signaling in vivo inhibits MEKK4 activity, whereas gain of Fgf20 function stimulates MEKK4 expression, suggesting that Fgf20 modulates MEKK4 activity to regulate cellular differentiation. Finally, we demonstrate, for the first time, that MEKK4 acts as a critical node to integrate FGF20-FGFR1 signaling responses to specifically influence HC development and that FGFR1 signaling through activation of MEKK4 is necessary for outer hair cell differentiation. Collectively, this study provides compelling evidence of an essential role for MEKK4 in inner ear morphogenesis and identifies the requirement of MEKK4 expression in regulating the specific response of FGFR1 during HC development and FGF20/FGFR1 signaling activated MEKK4 for normal sensory cell differentiation. SIGNIFICANCE STATEMENT Sensory hair cells (HCs) are the mechanoreceptors within the inner ear responsible for our sense of hearing. HCs are formed before birth, and mammals lack the ability to restore the sensory deficits associated with their loss. In this study, we show, for the first time, that MEKK4 signaling is essential for the development of normal cytoarchitecture and hearing function as MEKK4 signaling-deficient mice exhibit a significant reduction of HCs and a hearing loss. We also identify MEKK4 as a critical hub kinase for FGF20-FGFR1 signaling to induce HC differentiation in the mammalian cochlea. These results reveal a new paradigm in the regulation of HC differentiation and provide significant new insights into the mechanism of Fgf signaling governing HC formation.
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44
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Ren H, Guo W, Liu W, Gao W, Xie D, Yin T, Yang S, Ren J. DAPT mediates atoh1 expression to induce hair cell-like cells. Am J Transl Res 2016; 8:634-643. [PMID: 27158355 PMCID: PMC4846912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Accepted: 12/22/2015] [Indexed: 06/05/2023]
Abstract
Hearing loss is currently an incurable degenerative disease characterized by a paucity of hair cells (HCs), which cannot be spontaneously replaced in mammals. Recent technological advancements in gene therapy and local drug delivery have shed new light for hearing loss. Atoh1, also known as Math1, Hath1, and Cath1, is a proneural basic helix-loop-helix (bHLH) transcription factor that is essential for HC differentiation. At various stages in development, Atoh1 activity is sufficient to drive HC differentiation in the cochlea. Thus, Atoh1 related gene therapy is the most promising option for HC induction. DAPT, an inhibitor of Notch signaling, enhances the expression of Atoh1 indirectly, which in turn promotes the induction of a HC fate. Here, we show that DAPT cooperates with Atoh1 to synergistically promote HC fate in ependymal cells in vitro and promote hair cell regeneration in the cultured basilar membrane (BM) which mimics the microenvironment in vivo. Taken together, our findings demonstrated that DAPT is sufficient to induce HC-like cells via enhancing of the expression of Atoh1 to inhibit the progression of HC apoptosis and to induce new HC formation.
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Affiliation(s)
- Hongmiao Ren
- Otorhinolaryngology Hospital, The First Affiliated Hospital, Sun Yat-sen UniversityGuangzhou 510080, Guangdong, P.R. China
| | - Weiwei Guo
- Department of Otolaryngology Head and Neck Surgery, Institute of Otolaryngology, Chinese PLA General HospitalBeijing, China
| | - Wei Liu
- Department of Otolaryngology Head and Neck Surgery, The Second Xiangya Hospital, Central South UniversityNo. 139 Middle Renmin Road, Changsha 410011, Hunan, P.R. China
| | - Weiqiang Gao
- Renji-MedX Clinical Stem Cell Research Center, Renji Hospital, Shanghai Jiao Tong University School of MedicineShanghai, China
- Med-X Research Institute, Shanghai Jiao Tong UniversityShanghai, China
- Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of MedicineShanghai, China
| | - Dinghua Xie
- Department of Otolaryngology Head and Neck Surgery, The Second Xiangya Hospital, Central South UniversityNo. 139 Middle Renmin Road, Changsha 410011, Hunan, P.R. China
| | - Tuanfang Yin
- Department of Otolaryngology Head and Neck Surgery, The Second Xiangya Hospital, Central South UniversityNo. 139 Middle Renmin Road, Changsha 410011, Hunan, P.R. China
| | - Shiming Yang
- Department of Otolaryngology Head and Neck Surgery, Institute of Otolaryngology, Chinese PLA General HospitalBeijing, China
| | - Jihao Ren
- Department of Otolaryngology Head and Neck Surgery, The Second Xiangya Hospital, Central South UniversityNo. 139 Middle Renmin Road, Changsha 410011, Hunan, P.R. China
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45
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Basch ML, Brown RM, Jen H, Groves AK. Where hearing starts: the development of the mammalian cochlea. J Anat 2016; 228:233-54. [PMID: 26052920 PMCID: PMC4718162 DOI: 10.1111/joa.12314] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2015] [Indexed: 12/11/2022] Open
Abstract
The mammalian cochlea is a remarkable sensory organ, capable of perceiving sound over a range of 10(12) in pressure, and discriminating both infrasonic and ultrasonic frequencies in different species. The sensory hair cells of the mammalian cochlea are exquisitely sensitive, responding to atomic-level deflections at speeds on the order of tens of microseconds. The number and placement of hair cells are precisely determined during inner ear development, and a large number of developmental processes sculpt the shape, size and morphology of these cells along the length of the cochlear duct to make them optimally responsive to different sound frequencies. In this review, we briefly discuss the evolutionary origins of the mammalian cochlea, and then describe the successive developmental processes that lead to its induction, cell cycle exit, cellular patterning and the establishment of topologically distinct frequency responses along its length.
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Affiliation(s)
- Martin L. Basch
- Department of NeuroscienceBaylor College of MedicineHoustonTXUSA
| | - Rogers M. Brown
- Program in Developmental BiologyBaylor College of MedicineHoustonTXUSA
| | - Hsin‐I Jen
- Program in Developmental BiologyBaylor College of MedicineHoustonTXUSA
| | - Andrew K. Groves
- Department of NeuroscienceBaylor College of MedicineHoustonTXUSA
- Program in Developmental BiologyBaylor College of MedicineHoustonTXUSA
- Department of Molecular and Human GeneticsBaylor College of MedicineHoustonTXUSA
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46
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Huyghe A, Van den Ackerveken P, Sacheli R, Prévot PP, Thelen N, Renauld J, Thiry M, Delacroix L, Nguyen L, Malgrange B. MicroRNA-124 Regulates Cell Specification in the Cochlea through Modulation of Sfrp4/5. Cell Rep 2015; 13:31-42. [PMID: 26387953 DOI: 10.1016/j.celrep.2015.08.054] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 07/01/2015] [Accepted: 08/18/2015] [Indexed: 02/08/2023] Open
Abstract
The organ of Corti, the auditory organ of the mammalian inner ear, contains sensory hair cells and supporting cells that arise from a common sensory progenitor. The molecular bases allowing the specification of these progenitors remain elusive. In the present study, by combining microarray analyses with conditional deletion of Dicer in the developing inner ear, we identified that miR-124 controls cell fate in the developing organ of Corti. By targeting secreted frizzled-related protein 4 (Sfrp4) and Sfrp5, two inhibitors of the Wnt pathway, we showed that miR-124 controls the β-catenin-dependent and also the PCP-related non-canonical Wnt pathways that contribute to HC differentiation and polarization in the organ of Corti. Thus, our work emphasizes the importance of miR-124 as an epigenetic safeguard that fine-tunes the expression of genes critical for cell patterning during cochlear differentiation.
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Affiliation(s)
- Aurélia Huyghe
- GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium
| | | | - Rosalie Sacheli
- GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium
| | - Pierre-Paul Prévot
- GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium
| | - Nicolas Thelen
- GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium
| | - Justine Renauld
- GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium
| | - Marc Thiry
- GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium
| | - Laurence Delacroix
- GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium
| | - Laurent Nguyen
- GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium
| | - Brigitte Malgrange
- GIGA-Neurosciences, University of Liege, C.H.U. Sart Tilman, Liege 4000, Belgium.
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47
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Jahan I, Pan N, Kersigo J, Fritzsch B. Neurog1 can partially substitute for Atoh1 function in hair cell differentiation and maintenance during organ of Corti development. Development 2015. [PMID: 26209643 DOI: 10.1242/dev.123091] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Atoh1, a basic helix-loop-helix (bHLH) transcription factor (TF), is essential for the differentiation of hair cells (HCs), mechanotransducers that convert sound into auditory signals in the mammalian organ of Corti (OC). Previous work demonstrated that replacing mouse Atoh1 with the fly ortholog atonal rescues HC differentiation, indicating functional replacement by other bHLH genes. However, replacing Atoh1 with Neurog1 resulted in reduced HC differentiation compared with transient Atoh1 expression in a 'self-terminating' Atoh1 conditional null mouse (Atoh1-Cre; Atoh1(f/f)). We now show that combining Neurog1 in one allele with removal of floxed Atoh1 in a self-terminating conditional mutant (Atoh1-Cre; Atoh1(f/kiNeurog1)) mouse results in significantly more differentiated inner HCs and outer HCs that have a prolonged longevity of 9 months compared with Atoh1 self-terminating littermates. Stereocilia bundles are partially disorganized, disoriented and not HC type specific. Replacement of Atoh1 with Neurog1 maintains limited expression of Pou4f3 and Barhl1 and rescues HCs quantitatively, but not qualitatively. OC patterning and supporting cell differentiation are also partially disrupted. Diffusible factors involved in patterning are reduced (Fgf8) and factors involved in cell-cell interactions are affected (Jag1, Hes5). Despite the presence of many HCs with stereocilia these mice are deaf, possibly owing to HC and OC patterning defects. This study provides a novel approach to disrupt OC development through modulating the HC-specific intracellular TF network. The resulting disorganized OC indicates that normally differentiated HCs act as 'self-organizers' for OC development and that Atoh1 plays a crucial role to initiate HC stereocilia differentiation independently of HC viability.
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Affiliation(s)
- Israt Jahan
- Department of Biology, College of Liberal Arts & Sciences, University of Iowa, Iowa City, IA 52242, USA
| | - Ning Pan
- Department of Biology, College of Liberal Arts & Sciences, University of Iowa, Iowa City, IA 52242, USA
| | - Jennifer Kersigo
- Department of Biology, College of Liberal Arts & Sciences, University of Iowa, Iowa City, IA 52242, USA
| | - Bernd Fritzsch
- Department of Biology, College of Liberal Arts & Sciences, University of Iowa, Iowa City, IA 52242, USA
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48
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Atkinson PJ, Huarcaya Najarro E, Sayyid ZN, Cheng AG. Sensory hair cell development and regeneration: similarities and differences. Development 2015; 142:1561-71. [PMID: 25922522 DOI: 10.1242/dev.114926] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Sensory hair cells are mechanoreceptors of the auditory and vestibular systems and are crucial for hearing and balance. In adult mammals, auditory hair cells are unable to regenerate, and damage to these cells results in permanent hearing loss. By contrast, hair cells in the chick cochlea and the zebrafish lateral line are able to regenerate, prompting studies into the signaling pathways, morphogen gradients and transcription factors that regulate hair cell development and regeneration in various species. Here, we review these findings and discuss how various signaling pathways and factors function to modulate sensory hair cell development and regeneration. By comparing and contrasting development and regeneration, we also highlight the utility and limitations of using defined developmental cues to drive mammalian hair cell regeneration.
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Affiliation(s)
- Patrick J Atkinson
- Department of Otolaryngology - Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Elvis Huarcaya Najarro
- Department of Otolaryngology - Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Zahra N Sayyid
- Department of Otolaryngology - Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Alan G Cheng
- Department of Otolaryngology - Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
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49
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Fritzsch B, Pan N, Jahan I, Elliott KL. Inner ear development: building a spiral ganglion and an organ of Corti out of unspecified ectoderm. Cell Tissue Res 2015; 361:7-24. [PMID: 25381571 PMCID: PMC4426086 DOI: 10.1007/s00441-014-2031-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 10/09/2014] [Indexed: 01/21/2023]
Abstract
The mammalian inner ear develops from a placodal thickening into a complex labyrinth of ducts with five sensory organs specialized to detect position and movement in space. The mammalian ear also develops a spiraled cochlear duct containing the auditory organ, the organ of Corti (OC), specialized to translate sound into hearing. Development of the OC from a uniform sheet of ectoderm requires unparalleled precision in the topological developmental engineering of four different general cell types, namely sensory neurons, hair cells, supporting cells, and general otic epithelium, into a mosaic of ten distinctly recognizable cell types in and around the OC, each with a unique distribution. Moreover, the OC receives unique innervation by ear-derived spiral ganglion afferents and brainstem-derived motor neurons as efferents and requires neural-crest-derived Schwann cells to form myelin and neural-crest-derived cells to induce the stria vascularis. This transformation of a sheet of cells into a complicated interdigitating set of cells necessitates the orchestrated expression of multiple transcription factors that enable the cellular transformation from ectoderm into neurosensory cells forming the spiral ganglion neurons (SGNs), while simultaneously transforming the flat epithelium into a tube, the cochlear duct, housing the OC. In addition to the cellular and conformational changes forming the cochlear duct with the OC, changes in the surrounding periotic mesenchyme form passageways for sound to stimulate the OC. We review molecular developmental data, generated predominantly in mice, in order to integrate the well-described expression changes of transcription factors and their actions, as revealed in mutants, in the formation of SGNs and OC in the correct position and orientation with suitable innervation. Understanding the molecular basis of these developmental changes leading to the formation of the mammalian OC and highlighting the gaps in our knowledge might guide in vivo attempts to regenerate this most complicated cellular mosaic of the mammalian body for the reconstitution of hearing in a rapidly growing population of aging people suffering from hearing loss.
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Affiliation(s)
- Bernd Fritzsch
- College of Liberal Arts and Sciences, Department of Biology, University of Iowa, 143 BB, 123 Jefferson Avenue, Iowa City, IA 52242, USA,
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50
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Whitfield TT. Development of the inner ear. Curr Opin Genet Dev 2015; 32:112-8. [DOI: 10.1016/j.gde.2015.02.006] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 02/11/2015] [Accepted: 02/13/2015] [Indexed: 02/04/2023]
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