Chapter 16 Ectodermal Placodes and the Epidermis

Literature Cited

Aguirre, A., M. E. Rubio and V. Gallo. 2010. Notch and EGFR pathway interaction regulates neural stem cell number and self-renewal. Nature 467: 323­–327.
PubMed Link

Ahn, Y. 2015. Signaling in tooth, hair, and mammary placodes. Curr. Top. Dev. Biol. 111: 421–452.
PubMed Link

Ahn, Y., C. Sims, J. M. Logue, S. D. Weatherbee and R. Krumlauf. 2013. Lrp4 and wise interplay controls the formation and patterning of mammary and other skin appendage placodes by modulating Wnt signaling. Development 140: 583–593.
PubMed Link

Ahtiainen, L and 7 others. 2104. Directional cell migration, but not proliferation, drives hair placode morphogenesis. Dev. Cell 28: 588–602.
PubMed Link

Bailey, A. P., S. Bhattacharyya, M. Bronner-Fraser and A. Streit. 2006. Lens specification is the ground state of all sensory placodes, from which FGF promotes olfactory identity. Dev. Cell 11: 505–516.
PubMed Link

Bailey, T. J., H. El-Hodiri, L. Zhang, R. Shah, P. H. Mathers and M. Jamrich. 2004. Regulation of vertebrate eye development by Rx genes. Int. J. Dev. Biol. 48: 761–770.
PubMed Link

Baker, C. V. and M. Bronner-Fraser. 2001. Vertebrate cranial placodes. I. Embryonic induction. Dev. Biol. 232: 1–61.
PubMed Link

Baker, C. V., M. Bronner-Fraser, N. M. Le Douarin and M. A. Teillet. 1997. Early- and late-migrating cranial neural crest cell populations have equivalent developmental potential in vivo. Development 124: 3077–3087.
PubMed Link

Bakkers, J., M. Hild, C. Kramer, M. Furutani-Seiki and M. Hammerschmidt. 2002. Zebrafish DeltaNp63 is a direct target of BMP signaling and encodes a transcriptional repressor blocking neural specification in the ventral ectoderm. Dev. Cell 2: 617–627.
PubMed Link

Beazley, K. E., J. P. Canner and T. F. Linsenmayer. 2009. Developmental regulation of the nuclear ferritoid-ferritin complex of avian corneal epithelial cells: roles of systemic factors and thyroxine. Exp. Eye Res. 89854–8962.
PubMed Link

Begbie, J. and A. Graham. 2001. Integration between the epibranchial placodes and the hindbrain. Science 294: 595–598.
PubMed Link

Bhattacharyya, S., A. P. Baily, M. Bronner-Fraser and A. Streit. 2004. Segregation of lens and olfactory precursors from a common territory: Cell sorting and reciprocity of Dlx5 and Pax6 expression. Dev. Biol. 271: 403–414. 
PubMed Link

Biggs, L. C. and M. L. Mikkola. 2014. Early inductive events in ectodermal appendage morphogenesis. Semin. Cell Dev. Biol. 26: 11–21.
PubMed Link

Blanpain, C. and E. Fuchs. 2009. Epidermal homeostasis: A balancing act of stem cells in the skin. Nature Rev. Mol. Cell Biol. 10: 207–217.
PubMed Link

Breau, M. A. and S. Schneider-Maunoury. 2014. Mechanisms of cranial placode assembly. Int. J. Dev. Biol. 58: 9–19.
PubMed Link

Brown, K. E. and 6 others. 2010. Nlcam modulates midline convergence during anterior neural plate morphogenesis. Dev. Biol. 339: 14–25.
PubMed Link

Burmeister, M. and 13 others. 1996. Ocular retardation mouse caused by Chx10 homeobox null allele: Impaired retinal progenitor proliferation and bipolar cell differentiation.  Nature Genetics 12: 376–384.
PubMed Link

Cadieu, E. and 19 others. 2009. Coat variation in the domestic dog is governed by variants in three genes. Science 326: 150–153.
PubMed Link

Chauhan, B. K., M. Lou, Y. Zheng and R. A. Lang. 2011. Balanced Rac1 and RhoA activities regulate cell shape and drive invagination morphogenesis in epithelia. Proc. Natl. Acad. Sci. USA 108: 18289–18294.
PubMed Link

Chen, C. C. and 7 others. 2014. Regenerative hair waves in aging mice and extra-follicular modulators follistatin, dkk1, and sfrp4. J. Invest. Dermatol. 134: 2086–2096.
PubMed Link

Chiang, C., Y. Litingtung, E. Lee, K. E. Young, J. L. Cordoen, H. Westphal and P. A. Beachy. 1996. Cyclopia and axial patterning in mice lacking sonic hedgehog gene function. Nature 383: 407–413.
PubMed Link

Clevers, H. 2015. What is an adult stem cell? Science 350: 1319–1320.
PubMed Link

Cooper, M. K., J. A. Porter, K. E. Young and P. A. Beachy. 1998. Teratogen-mediated inhibition of target tissue response to hedgehog signaling. Science280: 1603–1607.
PubMed Link

Cotsarelis, G., S. Z. Cheng, G. Dong, T. T. Sun and R. M. Lavker. 1989. Existence of slow-cycling limbal epithelial basal cells that can be preferentially stimulated to proliferate: Implications on epithelial stem cells. Cell 57: 201–209.
PubMed Link

Cotsarelis, G., T.-T. Sun and R. M. Lavker. 1990. Label-retaining cells reside in the bulge area of pilosebaceous unit: Implications for follicular stem cells, hair cycle and skin carcinogenesis. Cell 61: 1329–1337.
PubMed Link

Coulombre, A. J. 1956. The role of intraocular pressure in the development of the chick eye. I. Control of eye size. J. Exp. Zool. 133: 211–225.

Coulombre, A. J. 1965. The eye. In R. DeHaan and H. Ursprung (eds.),Organogenesis. Holt, Rinehart & Winston, New York, pp. 217–251.

Cvekl, A. and E. R. Tamm. 2004. Anterior eye development and ocular mesenchyme: New insights from mouse models and human diseases. BioEssays26: 374–386.
PubMed Link

Decembrini, S. and 9 others. 2009. MiRNAs couple cell fate and developmental timing in retinal histogenesis. Proc. Natl. Acad. Sci. USA 106: 21179–21184.
PubMed Link

Decembrini, S., M. Andreazzoli, R. Vignali, G. Barsacchi and F. Cremisi. 2006. Timing the generation of distinct retinal cells by homeobox proteins. PLoS Biol. 4: e272.
PubMed Link

Dierks, C., S. Mömke, U. Philipp and O. Distl. 2013. Allelic heterogeneity of FGF5 mutations causes the long-hair phenotype in dogs. Anim. Genet. 44: 425–431.
PubMed Link

Donner, A. L., S. A. Lachke and R. L. Maas. 2006. Lens induction in vertebrates: Variations on a conserved theme of signaling events. Semin. Cell Dev. Biol. 17: 676–685.
PubMed Link

Dürnberger, H., B. Heuberger, P. Schwartz, G. Wasner and K. Kratochwil. 1978. Mesenchyme-mediated effect of testosterone on embryonic mammary epithelium. Cancer Res. 38: 4066–4070.
PubMed Link

Eiraku, M. and 8 others. 2011. Self-organizing optic-cup morphogenesis in three-dimensional culture. Nature 472: 51–56.
PubMed Link

Ezratty, E. J., N. Stokes, S. Chai, A. S. Shah, S. E. Williams and E. Fuchs. 2011. A role for the primary cilium in Notch signaling and epidermal differentiation during skin development. Cell 145: 1129–1141.
PubMed Link

Fuchs, E. and V. Horsley. 2008. More than one way to skin . . .  Genes Dev. 22: 976–985.
PubMed Link

Fuhrmann, S. 2010. Eye morphogenesis and patterning of the optic vesicle. Curr. Top. Dev. Biol. 93: 61–84.
PubMed Link

Gage, P. J., W. Rhoades, S. K. Prucka and T. Hjalt. 2005. Fate maps of neural crest and mesoderm in the mammalian eye.  Invest. Ophthalmol. Vis. Sci. 46: 4200–4208.
PubMed Link

Garza, L. A. and 10 others. 2011. Bald scalp in men with androgenetic alopecia retains hair follicle stem cells but lacks CD200-rich and CD34-positive hair follicle progenitor cells. J. Clin. Invest. 121: 613–622.
PubMed Link

Garza, L. A. and 14 others. 2012. Prostaglandin D2 inhibits hair growth and is elevated in bald scalp of men with androgenetic alopecia. Sci. Transl. Med.4:126ra34.
PubMed Link

Glaser, T., L. Jepeal, J. G. Edwards, S. R. Young, J. Favor and R. L. Maas. 1994.PAX6 gene dosage effect in a family with congenital cataracts, aniridia, anophthalmia and central nervous system defects. Nature Genet. 7: 463–471.
PubMed Link

Grainger, R. M. 1992. Embryonic lens induction: Shedding light on vertebrate tissue determination. Trends Genet. 8: 349–356.
PubMed Link

Groves, A. K. and LaBonne, C. 2014. Setting appropriate boundaries: Fate, patterning and competence at the neural plate border. Dev. Biol. 389: 2–12.
PubMed Link

Halder, G., P. Callaerts and W. J. Gehring. 1995. Induction of ectopic eyes by targeted expression of the eyeless gene in DrosophilaScience 267: 1788–1792.
PubMed Link

Hamburger, V. 1961. Experimental analysis of the dual origin of the trigeminal ganglion in the chick embryo. J. Exp. Zool. 148: 91–123.
PubMed Link

Hilfer, S. R. and J.-J. W. Yang. 1980. Accumulation of CPC-precipitable material at apical cell surfaces during formation of the optic cup. Anat. Rec. 197: 423–433.
PubMed Link

Hogg, N. A. S., D. J. Harrison and C. Tickle. 1983. Lumen formation in the mammary gland. J. Embryol. Exp. Morph. 73: 39–57.
PubMed Link

Hsu, Y. C., H. A. Pasolli and E. Fuchs. 2011. Dynamics between stem cells, niche, and progeny in the hair follicle. Cell 144: 92–105.
PubMed Link

Hsu, Y. C., L. Li and E. Fuchs. 2014. Emerging interactions between skin stem cells and their niches. Nature Med. 20: 847–856.
PubMed Link

Huh, S. H. 2013. Fgf20 governs formation of primary and secondary dermal condensations in developing hair follicles. Genes Dev. 27: 450–458.
PubMed Link

Huxley, T. H. 1882. On Science and Art in Relation to Education.
Link

Jacobson, A. G. 1963. The determination and positioning of the nose, lens, and ear III. Effects of reversing the anterior-posterior axis of the epidermis, neural plate,and neural fold. J. Exp. Zool. 154: 293–303. 
PubMed Link

Jacobson, A. G. 1966. Inductive processes in embryonic development. Science 152: 25–34.
PubMed Link

Janesick, A., J. Shiotsugu, M. Taketani and B. Blumberg. 2012. RIPPLY3 is a retinoic acid-inducible repressor required for setting the borders of the pre-placodal ectoderm. Development 139: 1213–1224.
PubMed Link

Järvinen, E., I. Salazar-Ciudad, W. Birchmeier, M. M. Taketo, J. Jernvall, and I. Thesleff. 2006. Continuous tooth generation in mouse is induced by activated epithelial Wnt/b-catenin signaling. Proc. Natl. Acad. Sci. USA 103: 18627–18632.
PubMed Link

Jernvall, J., T. Aberg, P. Kettunen, S. Keränen and I. Thesleff. 1998. The life history of an embryonic signaling center: BMP-4 induces p21 and is associated with apoptosis in the mouse tooth enamel knot. Development 125: 161–169.
PubMed Link

Johansson, J. A. and D. J. Headon. 2014. Regionalisation of the skin. Semin. Cell Dev. Biol. 26: 3–10.
PubMed Link

Johnston, M. C., D. M. Noden, R. D. Hazelton, J. L. Coulombre and A. J. Coulombre. 1979. Origins of avian ocular and periocular tissues. Exp. Eye Res. 29: 27–43.
PubMed Link

Johnstone, M. A. and D. M. Albert. 2002. Prostaglandin-induced hair growth. Surv. Ophthalmol. 47: S185–202.
PubMed Link

Jordan, T. and 7 others. 1992. The human PAX6 gene is mutated in two patients with aniridia. Nature Genet. 1: 328–332.
PubMed Link

Jussila, M. and I. Thesleff. 2012. Signaling networks regulating tooth organogenesis and regeneration, and the specification of dental mesenchymal and epithelial cell lineage. Cold Spring Harbor Persp. Biol. 4: a008425.
PubMed Link

Kanakubo, S., T. Nomura, K. Yamamura, J. Miyazaki, M. Tamai and N. Osumi. 2006. Abnormal migration and distribution of neural crest cells in Pax6 heterozygous mutant eye, a model for human eye diseases. Genes Cells 11: 919–933.
PubMed Link

Kaufman, K. D. 2002. Androgens and alopecia. Mol. Cell Endocr. 198: 89–95.
PubMed Link

Kelley, R. I. and 7 others. 1996. Holoprosencephaly in RSH/Smith-Lemli-Opitz syndrome: Does abnormal cholesterol metabolism affect the function of Sonic hedgehog? Am. J. Med. Genet. 66: 478–484.
PubMed Link

Kollar, E. J. 1970. The induction of hair follicles by embryonic dermal papillae. J. Invest. Derm. 55: 374–378.
PubMed Link

Kollar, E. J. and G. R. Baird. 1970. Tissue interactions in embryonic mouse tooth germs II. The inductive role of the dental papilla. J. Embryol. Exp. Morphol. 24: 173–186.
PubMed Link

Kondoh, H., M. Uchikawa and Y. Kamachi. 2004. Interplay of Pax6 and Sox2 in lens development as a paradigm of genetic switch mechanisms for cell differentiation. Int. J. Dev. Biol. 48: 819–827. 
PubMed Link

Kratochwil, K. 1985. Tissue combination and organ culture studies in the development of the embryonic mammary gland. Dev. Biol. 4: 315–333.
PubMed Link

Kratochwil, K. and P. Schwartz. 1976. Tissue interaction in androgen response of embryonic mammary rudiment of mouse: identification of target tissue for testosterone. Proc. Natl. Acad. Sci. USA 73: 4041–4044.
PubMed Link

Kurpakus, M. A., M. T. Maniaci and M. Esco. 1994. Expression of keratins K12, K4, and K14 during development of ocular surface epithelium. Curr. Eye Res. 13: 805–814.
PubMed Link

Ladher, R. K., K. U. Anakwe, A. L. Gurney, G. C. Schoenwolf and P. H. Francis-West. 2000. Identification of synergistic signals initiating inner ear development. Science 290: 1965–1967.
PubMed Link

Ladher, R. K., T. J. Wright, A.M. Moon, S. L. Mansour and G. C. Schoenwolf. 2005. FGF8 initiates inner ear induction in chick and mouse. Genes Dev. 19: 603–613.
PubMed Link

Lay, K., T. Kume and E. Fuchs. 2016. FOXC1 maintains the hair follicle stem cell niche and governs stem cell quiescence to preserve long-term tissue-regenerating potential. Proc. Natl. Acad. Sci. USA. pii: 201601569.
PubMed Link

Lechler, T. and E. Fuchs. 2005. Asymmetric cell divisions promote stratification and differentiation of mammalian skin. Nature 437: 275­–280.
PubMed Link

Levy, V., C. Lindon, Y. Zheng, B. D. Harfe and B. A. Morgan. 2007. Epidermal stem cells arise from the hair follicle after wounding. FASEB J. 21: 1358–1366.
PubMed Link

Linsenmayer, T. F., C. X. Cai, J. M. Millholland, K. E. Beazley and J. M. Fitch. 2005. Nuclear ferritin in corneal epithelial cells: tissue-specific nuclear transport and protection from UV-damage. Prog. Retin. Eye Res. 24:139–159.
PubMed Link

Liu, E. Y. and 14 others. 2008. Wnt/β-catenin signaling directs multiple stages of tooth morphogenesis. Dev. Biol. 313: 210–224.
PubMed Link

Mack, J. A., S. Anand and E. V. Maytin. 2005. Proliferation and cornification during development of the mammalian epidermis. Birth Def. Res. C Embryol. Today 75: 314–329.
PubMed Link

Mailleux, A. A., B. Spencer-Dene, C. Dillon and S. Bellusci. 2002. Role of FGF10/FGFR2b signaling during mammary gland development in the mouse embryo. Development 129: 53–60.
PubMed Link

Majo, F., A. Rochat, M. Nicolas, G. A. Jaoudé and Y. Barrandon. 2008. Oligopotent stem cells are distributed throughout the mammalian ocular surface.Nature 456: 250–254.
PubMed Link

Mammoto, T. and 10 others. 2011. Mechanochemical control of mesenchymal condensation and embryonic tooth organ formation. Dev. Cell 21: 758–769.
PubMed Link

Mascré, G. and 7 others. 2012. Distinct contribution of stem and progenitor cells to epidermal maintenance. Nature 489: 257–262.
PubMed Link

Meier, S. and E. D. Hay. 1974. Control of corneal differentiation by extracellular materials: Collagen as a promoter and stabilizer of epithelial stroma production. Dev. Biol. 38: 249–270.
PubMed Link

Mesa, K. R. and 9 others. 2015. Niche-induced cell death and epithelial phagocytosis regulate hair follicle stem cell pool. Nature 522: 94–97.
PubMed Link

Mikkola, M. L. 2008. TNF superfamily in skin appendage development. Cytokine Growth Factor Rev. 19: 219–230.
PubMed Link

Mina, M. and E. J. Kollar. 1987. The induction of odontogenesis in non-dental mesenchyme combined with early murine mandibular arch epithelium. Arch. Oral Biol. 32: 123–127.
PubMed Link

Montell, D. J. 2008. Morphogenetic cell movements: Diversity from modular mechanical properties. Science 322: 1502–1505.
PubMed Link

Moody, S. A. and LaMantia, A. S. 2015. Transcriptional regulation of cranial sensory placode development. Curr. Top. Dev. Biol. 111: 301–350.
PubMed Link

Morris, R. J. and C. S. Potten. 1999. Highly persistent lanbel-retaining cells in the hair follicles of mice and their fate following induction of anagen. J. Invest. Dermat. 112: 470–475.
PubMed Link

Mukhopadhyay, M. and 6 others. 2006. Dkk2 plays an essential role in the corneal fate of the ocular surface epithelium. Development 133: 2149–2154.
PubMed Link

Munne, P. M., M. Tummers, E. Järvinen, I. Thesleff and J. Jernvall. 2009. Tinkering with the inductive mesenchyme: Sostdc1 uncovers the role of dental mesenchyme in limiting tooth induction. Development 136: 393–402.
PubMed Link

Myung, P. S., M. Takeo, M. Ito and R. Atit. 2013. Epithelial Wnt ligand secretion is required for adult hair follicle growth and regeneration. J. Invest. Dermatol. 133: 31–34.
PubMed Link

Närhi, K., E. Järvinen, W. Birchmeier, M. M. Taketo, M. L. Mikkola and I. Thesleff. 2008. Sustained epithelial b-catenin activity induces precocious hair development but disrupts hair follicle down-growth and hair shaft formation. Development 135: 1019–1028.
PubMed Link

Närhi, K., M. Tummers, L. Ahtiainen, N. Itoh, I. Thesleff and M.L. Mikkola. 2012. Sostdc1 defines the size and number of skin appendage placodes. Dev. Biol. 364: 149–161.
PubMed Link

Nelson, A. M. and 12 others. 2015. dsRNA released by tissue damage activates TLR3 to drive skin regeneration. Cell Stem Cell 17: 139–151.
PubMed Link

Neubüser, A., H. Peters, R. Balling and G. R. Martin. 1997. Antagonistic interactions between FGF and BMP signaling pathways: A mechanism for positioning the sites of tooth formation. Cell 90: 247–255.
PubMed Link

Nguyen, B. and 14 others. 2006. Cross-regulation between Notch and p63 in keratinocyte commitment to differentiation. Genes Dev. 20: 1028–1042.
PubMed Link

Nguyen, M. and H. Arnheiter. 2000. Signaling and transcriptional regulation in early mammalian eye development: A link between FGF and MITF. Development127: 3581–3591.
PubMed Link

Nishimura, E. K. and 9 others. 2002. Dominant role of the niche in melanocyte stem-cell fate determination. Nature 416: 854–860. 
PubMed Link

Oakes, S. R., H. N. Hilton and C. J. Ormandy. 2006. The alveolar switch: Coordinating the proliferative cues and cell fate decisions that drive the formation of lobuloalveoli from ductal epithelium. Breast Cancer Res. 8: 207.
PubMed Link

O’Connell, D. J. and 9 others. 2012. A Wnt-BMP feedback circuit controls intertissue signaling dynamics in tooth organogenesis. Sci. Signal 5. doi: 10.1126/scisignal.2002414.ra4.
PubMed Link

Ogino, H., H. Ochi, H. M. Reza and K. Yasuda. 2012. Transcription factors involved in lens development from the preplacodal ectoderm. Dev. Biol. 363: 333–347.
PubMed Link

Ogino, H., M. Fisher and R. M. Grainger. 2008. Convergence of a head-field selector Otx2 and Notch signaling: A mechanism for lens specification. Development 135: 249–258.
PubMed Link

Panousopoulou, E. and J. B. A. Green. 2016. Invagination of ectodermal placodes is driven by intercalation-mediated contraction of the suprabasal tissue canopy. PLoS Biol. 14: e1002405.
PubMed Link

Papaconstantinou, J. 1967. Molecular aspects of lens cell differentiation. Science 156: 338–346.
PubMed Link

Patthey, C., T. Edlund and L. Gunhaga. 2009. Wnt-regulated temporal control of BMP exposure directs the choice between neural plate border and epidermal fate. Development 136: 73–83.
PubMed Link

Piatigorsky, J. 1981. Lens differentiation in vertebrates: A review of cellular and molecular features. Differentiation 19: 134–153.
PubMed Link

Pieper, M., G. W. Eagleson, W. Wosniok and G. Schlosser. 2011. Origin and segregation of cranial placodes in Xenopus laevisDev. Biol. 360: 257–275.
PubMed Link

Pispa, J. and I. Thesleff. 2003. Mechanisms of ectodermal organogenesis. Dev. Biol. 262: 195–205.
PubMed Link

Platt, J. B. 1896. Ontogenetic differentiation of the ectoderm in Necturus. Study II: Development of the peripheral nervous system. Quart. J. Micro. Sci. 38: 911–966.

Plikus, M. V., J. A. Mayer, D. de la Cruz, R. E. Baker, P. K. Maini, R. Maxson and C. M. Chuong. 2008. Cyclic dermal BMP signalling regulates stem cell activation during hair regeneration. Nature 451: 340–344.
PubMed Link

Propper, A. and L. Gomot. 1967. Tissue interactions during organogenesis of the mammary gland in the rabbit embryo. (Article in French). C. R. Acad. Sci. Hebd. Seances Acad. Sci. D. 264: 2573–2575.

Quiring, R., U. Walldorf, U. Kloter and W. J. Gehring. 1994. Homology of theeyeless gene of Drosophila to the Small eye gene in mice and Aniridia in humans. Science 265: 785–789.
PubMed Link

Raynaud, A. 1961. Morphogenesis of the mammary gland. In  S. K. Kon and A. T. Cowrie (eds.), Milk: The Mammary Gland and Its Secretion. Academic Press, New York, pp. 3–46.

Rendl, M., L. Polak and E. Fuchs. 2008. BMP signaling in dermal papilla cells is required for their hair follicle-inductive properties. Genes Dev. 22: 543–557.
PubMed Link

Reza, H. M., H. Nishi, K. Kataoka, Y. Takahashi and K. Yasuda. 2007. L-Maf regulates p27kip1 expression during chick lens fiber differentiation. Differentiation 75: 737–744.
PubMed Link

Rinn, J. L. and 10 others. 2008. A dermal HOX transcriptional program regulates site-specific epidermal fate. Genes Dev. 22: 303–307.
PubMed Link

Rios, A. C., N. Y. Fu, G. J. Lindeman and J. E. Visvader. 2014. In situ identification of bipotent stem cells in the mammary gland. Nature 506: 322–327.
PubMed Link

Roessler, E. and 7 others. 1996. Mutations in the human Sonic hedgehog gene cause holoprosencephaly. Nature Genet. 14: 357–360.
PubMed Link

Rompolas, P., K. R. Mesa and V. Greco. 2013. Spatial organization within a niche as a determinant of stem-cell fate. Nature 502: 513–518.
PubMed Link

Saha, M. S., C. L. Spann and R. M. Grainger. 1989. Embryonic lens induction: More than meets the optic vesicle. Cell Diff. Dev. 28: 153–172.
PubMed Link

Sasaki, S., Y. Hozumi and S. Kondo. 2005. Influence of prostaglandin F2a and its analogues on hair regrowth and follicular melanogenesis in a murine model. Exp. Dermatol. 14: 323–328.
PubMed Link

Schlosser, G. 2005. Evolutionary origins of vertebrate placodes: Insights from developmental studies and from comparisons with other deuterostomes. J. Exp. Zool. 304B: 347–399.
PubMed Link

Schlosser, G. 2010. Making senses: Development of vertebrate cranial placodes. Int. Rev. Cell Molec. Biol. 283: 129–234.
PubMed Link

Schlosser, G. and K. Ahrens. 2004. Molecular anatomy of placode development in Xenopus laevisDev. Biol. 271: 439–466. 
PubMed Link

Sennett, R. and M. Rendl. 2012. Mesenchymal-epithelial interactions during hair follicle morphogenesis and cycling. Semin. Cell Dev. Biol. 23: 917–927.
PubMed Link

Snippert, H. J. and 12 others. 2010. Lgr6 marks stem cells in the hair follicle that generate all cell lineages of the skin. Science 327: 1385–1389.
PubMed Link

St. Johnston, D. and B. Sanson. 2011. Epithelial polarity and morphogenesis. Curr. Opin. Cell Biol. 23: 540–546.
PubMed Link

Sternlicht, M. D., H. Kouros-Meir, P. Liu and Z. Werb. 2006. Hormonal and local control of mammary branching morphogenesis. Differentiation 74: 365–381.
PubMed Link

Stöhr, P. 1903. Anat. Hefte 23: 1–66; quoted in A. Christiano 2004. Epithelial stem cells: Stepping out of their niche. Cell 118: 530–532. 
PubMed Link

Streit, A. 2004. Early development of the cranial sensory nervous system: From a common field to individual placodes. Dev. Biol. 276: 1–15. 
PubMed Link

Streit, A. 2008. The cranial sensory nervous system: Specification of sensory progenitors and placodes. The Stem Cell Research Community, doi/10.3824/stembook.1.31.1.
Link

Tétreault, N., M. P. Champagne and G. Bernier. 2009. The LIM homeobox transcription factor Lhx2 is required to specify the retina field and synergistically cooperates with Pax6 for Six6 trans-activation. Dev. Biol. 327: 541–550.
PubMed Link

Taylor, G., M. S. Lehrer, P. J. Jensen, T. T. Sun and R. M. Lavker. 2000. Involvement of follicular stem cells in forming not only the follicle but also the epidermis. Cell 102: 451–461.
PubMed Link

Thesleff, I. and M. Tummers. 2009. Tooth organogenesis and regeneration. StemBook [Internet]. Cambridge (MA): Harvard Stem Cell Institute.
PubMed Link

Trumpp, A., M. J. Depew, J. L. Rubenstein, J. M. Bishop and G. R. Martin. 1999. Cre-mediated gene inactivation demonstrates that FGF8 is required for cell survival and patterning of the first branchial arch. Genes Dev. 13: 3136–3148.
PubMed Link

Truong, A. B. and P. A. Khavari. 2007. Control of keratinocyte proliferation and differentiation by p63. Cell Cycle 6: 295–299.
PubMed Link

Tsai, R. J., L. M. Li and J. K. Chen. 2000. Reconstruction of damaged corneas by transplantation of autologous limbal epithelial cells. New Engl. J. Med. 343: 86–93.
PubMed Link

Turner, D. L and C. L. Cepko. 1987. A common progenitor for neurons and glia persists in rat retina late in development. Nature 328: 131-136.
PubMed Link

Vaahtokari, A., T. Aberg, J. Jernvall, S. Keränen and I. Thesleff. 1996. The enamel knot as a signaling center in the developing mouse tooth. Mech. Dev. 54: 39–43.
PubMed Link

Vainio, S., I. Karavanova, A. Jowett and I. Thesleff. 1993. Identification of BMP-4 as a signal mediating secondary induction between epithelial and mesenchymal tissues during early tooth development Cell 75: 45–58.
PubMed Link

Van Genderen, R.M. and 6 others. 1994. Development of several organs that require inductive epithelial–mesenchymal interactions is impaired in LEF-1-deficient mice. Genes Dev. 8: 2691–2703.
PubMed Link

Veltmaat, J. M. and 10 others. 2006. Gli3-mediated somitic Fgf10 expression gradients are required for the induction and patterning of mammary epithelium along the embryonic axes. Development 133: 2325–2335.
PubMed Link

Visvader, J. E. and J. Stingl. 2014. Mammary stem cells and the differentiation hierarchy: current status and perspectives. Genes Dev. 28: 1143–1158.
PubMed Link

Wang, D. and 6 others. 2015. Identification of multipotent mammary stem cells by protein C receptor expression. Nature 517: 81–84.
PubMed Link

Wang, L., J. A. Siegenthaler, R. D. Dowell and R. Yi. 2016. Foxc1 reinforces quiescence in self-renewing hair follicle stem cells. Science 351: 613–617.
PubMed Link

Wang, T. and 7 others. 2015. Alpaca fiber growth is mediated by microRNA let-7b via down-regulation of target gene FgfF5. Genet. Mol. Res. 14: 13754–13763.
PubMed Link

Weston, J. and S. L. Butler. 1966. Temporal factors affecting localization of neural crest cells in the chicken embryo. Dev. Biol. 14: 246–266.
PubMed Link

Williams, S. E., S. Beronja, H. A. Pasolli and E. Fuchs E. 2011. Asymmetric cell divisions promote Notch-dependent epidermal differentiation. Nature 470: 353–358.
PubMed Link

Wu, P. and 10 others. 2013. Specialized stem cell niche enables repetitive renewal of alligator teeth. Proc. Natl. Acad. Sci. USA 110: E2009–2018.
PubMed Link

Yamamoto, Y., D. W. Stock and W. R. Jeffery. 2004. Hedgehog signaling controls eye degeneration in blind cavefish. Nature 431: 844–847.
PubMed Link

Yamamoto, Y., M. S. Byerly, W. R. Jackman and W. R. Jeffery. 2009. Pleiotropic functions of embryonic Sonic hedgehog expression link jaw and taste bud amplification with eye loss during cavefish evolution. Dev. Biol. 330: 200–211.
PubMed Link

Yang, J., M. V. Plikus and N. L. Komarova. 2015. The role of symmetric stem cell divisions in tissue homeostasis. PLoS Comput. Biol. 11: e1004629.
PubMed Link

Yang, X.-J. 2004. Roles of cell-extrinsic growth factors in vertebrate eye pattern formation and retinogenesis. Sem. Cell Dev. Biol. 15: 91–103. 
PubMed Link

Zhang, Y. and 12 others. 2008. Activation of b-catenin signaling programs embryonic epidermis to hair follicle fate. Development 135: 2161–2172.
PubMed Link

Zuber, M. E. 2010. Mechanisms regulating eye field specification and early eye formation. Curr. Topics Dev. Biol. 93: 48–53.
PubMed Link

Zuber, M. E., G. Gestri, A. S. Viczian, G. Barsacchi and W. A. Harris. 2003. Specification of the vertebrate eye by a network of eye field transcription factors. Development 130: 5155–5167.
PubMed Link