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Holthaus KB, Eckhart L. Development-Associated Genes of the Epidermal Differentiation Complex (EDC). J Dev Biol 2024; 12:4. [PMID: 38248869 PMCID: PMC10801484 DOI: 10.3390/jdb12010004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 12/28/2023] [Accepted: 01/10/2024] [Indexed: 01/23/2024] Open
Abstract
The epidermal differentiation complex (EDC) is a cluster of genes that encode protein components of the outermost layers of the epidermis in mammals, reptiles and birds. The development of the stratified epidermis from a single-layered ectoderm involves an embryo-specific superficial cell layer, the periderm. An additional layer, the subperiderm, develops in crocodilians and over scutate scales of birds. Here, we review the expression of EDC genes during embryonic development. Several EDC genes are expressed predominantly or exclusively in embryo-specific cell layers, whereas others are confined to the epidermal layers that are maintained in postnatal skin. The S100 fused-type proteins scaffoldin and trichohyalin are expressed in the avian and mammalian periderm, respectively. Scaffoldin forms the so-called periderm granules, which are histological markers of the periderm in birds. Epidermal differentiation cysteine-rich protein (EDCRP) and epidermal differentiation protein containing DPCC motifs (EDDM) are expressed in the avian subperiderm where they are supposed to undergo cross-linking via disulfide bonds. Furthermore, a histidine-rich epidermal differentiation protein and feather-type corneous beta-proteins, also known as beta-keratins, are expressed in the subperiderm. The accumulating evidence for roles of EDC genes in the development of the epidermis has implications on the evolutionary diversification of the skin in amniotes.
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Affiliation(s)
| | - Leopold Eckhart
- Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria
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2
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Alibardi L. Microscopic and immunohistochemical study on the cornification of the developing beak in the turtleEmydura macquarii. J Morphol 2016; 277:1309-19. [DOI: 10.1002/jmor.20576] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 05/18/2016] [Accepted: 06/23/2016] [Indexed: 01/23/2023]
Affiliation(s)
- Lorenzo Alibardi
- Comparative Histolab and Department of Bigea; Università Di Bologna; via Selmi 3 Bologna 40126 Italy
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3
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Musser JM, Wagner GP, Prum RO. Nuclear β-catenin localization supports homology of feathers, avian scutate scales, and alligator scales in early development. Evol Dev 2015; 17:185-94. [PMID: 25963196 DOI: 10.1111/ede.12123] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Feathers are an evolutionary novelty found in all extant birds. Despite recent progress investigating feather development and a revolution in dinosaur paleontology, the relationship of feathers to other amniote skin appendages, particularly reptile scales, remains unclear. Disagreement arises primarily from the observation that feathers and avian scutate scales exhibit an anatomical placode-defined as an epidermal thickening-in early development, whereas alligator and other avian scales do not. To investigate the homology of feathers and archosaur scales we examined patterns of nuclear β-catenin localization during early development of feathers and different bird and alligator scales. In birds, nuclear β-catenin is first localized to the feather placode, and then exhibits a dynamic pattern of localization in both epidermis and dermis of the feather bud. We found that asymmetric avian scutate scales and alligator scales share similar patterns of nuclear β-catenin localization with feathers. This supports the hypothesis that feathers, scutate scales, and alligator scales are homologous during early developmental stages, and are derived from early developmental stages of an asymmetric scale present in the archosaur ancestor. Furthermore, given that the earliest stage of β-catenin localization in feathers and archosaur scales is also found in placodes of several mammalian skin appendages, including hair and mammary glands, we hypothesize that a common skin appendage placode originated in the common ancestor of all amniotes. We suggest a skin placode should not be defined by anatomical features, but as a local, organized molecular signaling center from which an epidermal appendage develops.
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Affiliation(s)
- Jacob M Musser
- Department of Ecology and Evolutionary Biology, and Peabody Museum of Natural History, Yale University, 21 Sachem St, New Haven, CT 06511, USA.,Systems Biology Institute, Yale University, 840 West Campus Drive, West Haven, CT 06516, USA
| | - Günter P Wagner
- Department of Ecology and Evolutionary Biology, and Peabody Museum of Natural History, Yale University, 21 Sachem St, New Haven, CT 06511, USA.,Systems Biology Institute, Yale University, 840 West Campus Drive, West Haven, CT 06516, USA
| | - Richard O Prum
- Department of Ecology and Evolutionary Biology, and Peabody Museum of Natural History, Yale University, 21 Sachem St, New Haven, CT 06511, USA
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4
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Alibardi L, Minelli D. Sites of cell proliferation during scute morphogenesis in turtle and alligator are different from those of lepidosaurian scales. ACTA ZOOL-STOCKHOLM 2014. [DOI: 10.1111/azo.12114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Lorenzo Alibardi
- Comparative Histolab and Department of Bigea; University of Bologna; via Semi 3 Bologna 40126 Italy
| | - Daniela Minelli
- Comparative Histolab and Department of Bigea; University of Bologna; via Semi 3 Bologna 40126 Italy
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5
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Sawyer RH, Rogers L, Washington L, Glenn TC, Knapp LW. Evolutionary origin of the feather epidermis. Dev Dyn 2005; 232:256-67. [PMID: 15637693 DOI: 10.1002/dvdy.20291] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The formation of scales and feathers in reptiles and birds has fascinated biologists for decades. How might the developmental processes involved in the evolution of the amniote ectoderm be interpreted to shed light on the evolution of integumental appendages? An Evo-Devo approach to this question is proving essential to understand the observation that there is homology between the transient embryonic layers covering the scale epidermis of alligators and birds and the epidermal cell populations of embryonic feather filaments. Whereas the embryonic layers of scutate scales are sloughed off at hatching, that their homologues persist in feathers demonstrates that the predecessors of birds took advantage of the ability of their ectoderm to generate embryonic layers by recruiting them to make the epidermis of the embryonic feather filament. Furthermore, observations on mutant chickens with altered scale and feather development (Abbott and Asmundson [1957] J. Hered. 18:63-70; Abbott [1965] Poult. Sci. 44:1347; Abbott [1967] Methods in developmental biology. New York: Thomas Y. Crowell) suggest that the ectodermal placodes of feathers, which direct the formation of unique dermal condensations and subsequently appendage outgrowth, provided the mechanism by which the developmental processes generating the embryonic layers diverged during evolution to support the morphogenesis of the epidermis of the primitive feather filament with its barb ridges.
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Affiliation(s)
- Roger H Sawyer
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29802, USA.
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6
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Alibardi L. Dermo-epidermal interactions in reptilian scales: Speculations on the evolution of scales, feathers, and hairs. ACTA ACUST UNITED AC 2004; 302:365-83. [PMID: 15287101 DOI: 10.1002/jez.b.20028] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The dermal influence on the epidermis during scale formation in reptiles is poorly known. Cells of the superficial dermis are not homogeneously distributed beneath the epidermis, but are instead connected to specific areas of the epidermis. Dermal cells are joined temporarily or cyclically through the basement membrane, with the reactive region of the epidermis forming specific regions of dermo-epidermal interactions. In these regions morphoregulatory molecules may be exchanged between the dermis and the connected epidermis. Possible changes in the localization of these regions in the skin may result in the production of different appendages, in accordance with the genetic makeup of the epidermis in each species. Regions of dermo-epidermal interactions seem to move their position during development. A hypothesis on the development and evolution of scales, hairs, and feathers from sarcopterigian fish to amniotes is presented, based on the different localization and extension of regions of dermo-epidermal interactions in the skin. It is hypothesized that, during phylogenesis, possible variations in the localization and extension of these regions, from the large scales of basic amniotes to those of sauropsid amniotes, may have originated scales with hard (beta)-keratin. In extant reptiles, extended regions of dermo-epidermal interaction form most of the expanse of outer scale surface. It is hypothesized that the reduction of large regions of dermo-epidermal interactions into small areas in the skin were the origin of dermal condensations. In mammals, small regions of dermo-epidermal interactions have invaginated, forming the dermal papilla with the associated hair matrix epidermis. In birds, small regions of dermo-epidermal interactions have reduced the original scale surface of archosaurian scales, forming the dermal papilla. The latter has invaginated in association with the collar epidermis from which feathers were produced.
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Affiliation(s)
- Lorenzo Alibardi
- Dipartimento di Biologia evoluzionistica sperimentale, University of Bologna, via Selmi 3, 40126 Bologna, Italy.
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7
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Sawyer RH, Knapp LW. Avian skin development and the evolutionary origin of feathers. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2003; 298:57-72. [PMID: 12949769 DOI: 10.1002/jez.b.26] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The discovery of several dinosaurs with filamentous integumentary appendages of different morphologies has stimulated models for the evolutionary origin of feathers. In order to understand these models, knowledge of the development of the avian integument must be put into an evolutionary context. Thus, we present a review of avian scale and feather development, which summarizes the morphogenetic events involved, as well as the expression of the beta (beta) keratin multigene family that characterizes the epidermal appendages of reptiles and birds. First we review information on the evolution of the ectodermal epidermis and its beta (beta) keratins. Then we examine the morphogenesis of scutate scales and feathers including studies in which the extraembryonic ectoderm of the chorion is used to examine dermal induction. We also present studies on the scaleless (sc) mutant, and, because of the recent discovery of "four-winged" dinosaurs, we review earlier studies of a chicken strain, Silkie, that expresses ptilopody (pti), "feathered feet." We conclude that the ability of the ectodermal epidermis to generate discrete cell populations capable of forming functional structural elements consisting of specific members of the beta keratin multigene family was a plesiomorphic feature of the archosaurian ancestor of crocodilians and birds. Evidence suggests that the discrete epidermal lineages that make up the embryonic feather filament of extant birds are homologous with similar embryonic lineages of the developing scutate scales of birds and the scales of alligators. We believe that the early expression of conserved signaling modules in the embryonic skin of the avian ancestor led to the early morphogenesis of the embryonic feather filament, with its periderm, sheath, and barb ridge lineages forming the first protofeather. Invagination of the epidermis of the protofeather led to formation of the follicle providing for feather renewal and diversification. The observations that scale formation in birds involves an inhibition of feather formation coupled with observations on the feathered feet of the scaleless (High-line) and Silkie strains support the view that the ancestor of modern birds may have had feathered hind limbs similar to those recently discovered in nonavian dromaeosaurids. And finally, our recent observation on the bristles of the wild turkey beard raises the possibility that similar integumentary appendages may have adorned nonavian dinosaurs, and thus all filamentous integumentary appendages may not be homologous to modern feathers.
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Affiliation(s)
- Roger H Sawyer
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208, USA
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Sawyer RH, Washington LD, Salvatore BA, Glenn TC, Knapp LW. Origin of archosaurian integumentary appendages: the bristles of the wild turkey beard express feather-type beta keratins. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2003; 297:27-34. [PMID: 12955841 DOI: 10.1002/jez.b.17] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The discovery that structurally unique "filamentous integumentary appendages" are associated with several different non-avian dinosaurs continues to stimulate the development of models to explain the evolutionary origin of feathers. Taking the phylogenetic relationships of the non-avian dinosaurs into consideration, some models propose that the "filamentous integumentary appendages" represent intermediate stages in the sequential evolution of feathers. Here we present observations on a unique integumentary structure, the bristle of the wild turkey beard, and suggest that this non-feather appendage provides another explanation for some of the "filamentous integumentary appendages." Unlike feathers, beard bristles grow continuously from finger-like outgrows of the integument lacking follicles. We find that these beard bristles, which show simple branching, are hollow, distally, and express the feather-type beta keratins. The significance of these observations to explanations for the evolution of archosaurian integumentary appendages is discussed.
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Affiliation(s)
- Roger H Sawyer
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA.
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Sawyer RH, Salvatore BA, Potylicki TTF, French JO, Glenn TC, Knapp LW. Origin of feathers: Feather beta (beta) keratins are expressed in discrete epidermal cell populations of embryonic scutate scales. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2003; 295:12-24. [PMID: 12548540 DOI: 10.1002/jez.b.5] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The feathers of birds develop from embryonic epidermal lineages that differentiate during outgrowth of the feather germ. Independent cell populations also form an embryonic epidermis on scutate scales, which consists of peridermal layers, a subperiderm, and an alpha stratum. Using an antiserum (anti-FbetaK) developed to react specifically with the beta (beta) keratins of feathers, we find that the feather-type beta keratins are expressed in the subperiderm cells of embryonic scutate scales, as well as the barb ridge lineages of the feather. However, unlike the subperiderm of scales, which is lost at hatching, the cells of barb ridges, in conjunction with adjacent cell populations, give rise to the structural elements of the feather. The observation that an embryonic epidermis, consisting of peridermal and subperidermal layers, also characterizes alligator scales (Thompson, 2001. J Anat 198:265-282) suggests that the epidermal populations of the scales and feathers of avian embryos are homologous with those forming the embryonic epidermis of alligators. While the embryonic epidermal populations of archosaurian scales are discarded at hatching, those of the feather germ differentiate into the periderm, sheath, barb ridges, axial plates, barbules, and marginal plates of the embryonic feather filament. We propose that the development of the embryonic feather filament provides a model for the evolution of the first protofeather. Furthermore, we hypothesize that invagination of the epidermal lineages of the feather filament, namely the barb ridges, initiated the formation of the follicle, which then allowed continuous renewal of the feather epidermal lineages, and the evolution of diverse feather forms.
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Affiliation(s)
- Roger H Sawyer
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208, USA.
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10
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Obinata A, Akimoto Y, Omoto Y, Hirano H. Expression of Hex homeobox gene during skin development: Increase in epidermal cell proliferation by transfecting the Hex to the dermis. Dev Growth Differ 2002; 44:281-92. [PMID: 12175363 DOI: 10.1046/j.1440-169x.2002.00642.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A number of homeobox genes have been found to be expressed in skin and its appendages, such as scale and feather, and appear to be candidates for the regulation of the development of these tissues. We report that the proline-rich divergent homeobox gene Hex is expressed during development of chick embryonic skin and its appendages (scale and feather). In situ hybridization analysis revealed that, during development of the skin, a transient expression of the Hex gene was observed. While the expression of Hex in the dermis was closely correlated with proliferation activity of epidermal basal cells, that in the epidermis was related to a suppression of epidermal differentiation. When dermal fibroblasts were transfected with Hex, stimulation of both DNA synthesis and proliferation of the epidermal cells followed by two-fold scale ridge elongation and increase in epidermal area was observed during culture of the skin, whereas epidemal keratinization was not affected. This is the first study to demonstrate that Hex is expressed during development of the skin and its appendages and that its expression in the dermal cells regulates epidermal cell proliferation through epithelial mesenchymal interaction.
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Affiliation(s)
- Akiko Obinata
- Department of Physiological Chemistry, Faculty of Pharmaceutical, Sciences, Teikyo University, Sagamiko, Kanagawa 199-0195, Japan.
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11
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Alibardi L, Thompson MB. Scale morphogenesis and ultrastructure of dermis during embryonic development in the alligator (Alligator mississippiensis, Crocodilia, Reptilia). ACTA ZOOL-STOCKHOLM 2001. [DOI: 10.1046/j.1463-6395.2000.00063.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Sawyer RH, Glenn T, French JO, Mays B, Shames RB, Barnes, Jr. GL, Rhodes W, Ishikawa Y. The Expression of Beta (β) Keratins in the Epidermal Appendages of Reptiles and Birds1. ACTA ACUST UNITED AC 2000. [DOI: 10.1668/0003-1569(2000)040[0530:teobki]2.0.co;2] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Sawyer RH, Glenn T, French JO, Mays B, Shames RB, Barnes GL, Rhodes W, Ishikawa Y. The Expression of Beta (β) Keratins in the Epidermal Appendages of Reptiles and Birds. ACTA ACUST UNITED AC 2000. [DOI: 10.1093/icb/40.4.530] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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14
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Barnes GL, Sawyer RH. Histidine-rich protein B of embryonic feathers is present in the transient embryonic layers of scutate scales. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1995; 271:307-14. [PMID: 7722473 DOI: 10.1002/jez.1402710408] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Based on its amino acid composition and N-terminal sequence, a polypeptide (HRP-B) has been identified as a member of the avian histidine-rich protein (HRP) family. An antiserum against HRP-B has been used to localize this polypeptide in developing feathers and scales of chick embryos. HRP-B was first detectable in the barb ridge cells of feathers at 13 days of incubation and progressively appeared in the distal/proximal and peripheral/central gradients observed previously for the feather-type beta keratins in developing feathers. The HRP-B polypeptide was detected only in the embryonic layers of scutate scales. It first appeared at 16 days of incubation and was not found in the differentiated beta strata of these scales. At no time during the development of reticulate scales or apteric skin regions did the epidermal cells or cells of the embryonic layers express HRP-B. The transient expression of HRP-B by the embryonic layers of the scutate scale epidermis is discussed in light of the feather-forming potential of the presumptive epidermis of the scutate scale-forming region.
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Affiliation(s)
- G L Barnes
- Department of Biological Sciences, University of South Carolina, Columbia 29208
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Knapp LW, Shames RB, Barnes GL, Sawyer RH. Region-specific patterns of beta keratin expression during avian skin development. Dev Dyn 1993; 196:283-90. [PMID: 7693054 DOI: 10.1002/aja.1001960411] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The transient embryonic layers primarily composed of a periderm and subperiderm cover most regions of the chick embryo and are the first suprabasal cell layers covering the body ectoderm. This study presents evidence for regional variation in the expression of beta keratin in the embryonic layers. Here we show that the embryonic layers covering the anterior metatarsal region of the chicken hindlimb (scutate scale forming region) produce several members of the beta keratin family of polypeptides, designated beta (beta) 1-7. These specific polypeptides are later expressed in this region exclusively in the thick, cornified beta strata of mature scutate scales. In contrast to this sequence of events, the embryonic layers overlying the epidermis of the ventral foot pad (reticulate scale-forming region) and those covering the epidermis in apteric regions of the body produce beta keratin polypeptides beta 1-3 and beta 2,3, respectively, but no subsequent expression of these proteins occurs in the mature epidermises of these regions. Furthermore, we find that the embryonic layers of the skin overlying the anterior metatarsal region of birds homozygous for the mutation "scaleless" (sc/sc), which completely lack scutate scales, produce the same members of the beta keratin family, beta 1-7, as the embryonic layers and beta strata of normal scutate scales. Thus, the accumulation of specific beta keratin polypeptides in the developing anterior metatarsal region appears to occur in two distinct phases; first, an early region-specific expression in cells of the embryonic layers followed by a second phase of expression which occurs in conjunction with appendage morphogenesis.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- L W Knapp
- Department of Biological Sciences, University of South Carolina, Columbia 29208
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17
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Abstract
Germinative cells of the scutate scale epidermis from 15-day embryos are committed to appendage-specific, beta stratum formation in association with a foreign dermis. Commitment precedes the time (17 days of development) at which beta strata are actually present in their site-specific locations along the outer surface of each scutate scale. This observation suggested the possibility that commitment to beta stratum formation might be occurring as the outer epidermal surface of each scutate scale first becomes established between 12 and 13 days of development. It is at this time that the scale epidermis loses its ability to participate in feather morphogenesis and cell proliferation becomes restricted to a true stratum basale. To examined the ability of the presumptive scutate scale epidermis to generate beta strata in the absence of the inductive scutate scale dermis, scutate scale epidermis from 11-, 12-, and 13-day embryos was recombined with 15-day reticulate scale dermis and grown for 7 or 9 days. The dermis of reticulate scales does not induce beta stratum formation, but it does support differentiation of a beta stratum by the determined 15-day scutate scale epidermis. Using immunohistological and biochemical analyses of beta-keratins, we find that each of these presumptive scutate scale epidermises is competent to generate appendage-specific beta strata in the absence of the scutate scale dermis. This determination is occurring prior to scale ridge morphogenesis and differentiation of the epidermis into the distinct outer and inner epidermal surfaces of the scale ridge. The restricted distribution of beta strata to the apical domes of individual reticulate-like scales demonstrates that the germinative cells of the committed epidermises are responding to patterned cues. This study also suggests that all basal cells of the presumptive scutate scale epidermis are initially endowed with the ability to generate cells that form a beta stratum.
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Affiliation(s)
- J Zeltinger
- Department of Biological Sciences, University of South Carolina, Columbia 29208
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18
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Shames RB, Jennings AG, Sawyer RH. The initial expression and patterned appearance of tenascin in scutate scales is absent from the dermis of the scaleless (sc/sc) chicken. Dev Biol 1991; 147:174-86. [PMID: 1715300 DOI: 10.1016/s0012-1606(05)80016-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Morphogenesis of the anterior metatarsal skin (scutate scale region), from 9.5 to 12 days of development, results in the formation of orderly patterned scale ridges. It is after the initial formation of the Definitive Scale Ridge that the characteristic outer and inner epidermal surfaces differentiate. The hard, plate-like beta stratum, with its unique beta keratins, characterizes the epidermis of the outer surface, while the epidermis of the inner surface elaborates an alpha stratum. The anterior metatarsal region of the scaleless mutant does not undergo scale morphogenesis. Therefore, scale ridges do not form nor do the outer and inner epidermal surfaces with their characteristic beta and alpha strata. We have found that the extracellular matrix molecule, tenascin, first appears in the scutate scale dermis at 12 days of development when the scale ridge is established. Tenascin is found in the dermis only under the scale ridge and is not associated with the dermal-epidermal junction. Tenascin is not found in scaleless anterior metatarsal dermis at this time. As outgrowth of the Definitive Scale Ridge takes place, tenascin distribution correlates closely with the formation of the outer epidermal surface of each scale ridge. By 16 days of development tenascin is also found in close association with the dermal-epidermal junction. Tenascin does not appear in scaleless anterior metatarsal dermis until 16 days of development and then it is randomly and sparsely distributed at the dermal-epidermal junction. Tenascin's initial appearance and pattern of distribution in the scutate scale dermis and its abnormal expression in the scaleless dermis suggest that morphogenesis plays a significant role in regulation of its expression.
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Affiliation(s)
- R B Shames
- Department of Biological Sciences, University of South Carolina, Columbia 29208
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Zeltinger J, Sawyer RH. Avian scale development. XIII. Epidermal germinative cells are committed to appendage-specific differentiation and respond to patterned cues in the dermis. Dev Biol 1991; 144:335-52. [PMID: 1707017 DOI: 10.1016/0012-1606(91)90426-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The ability of the germinative cell population of scutate scale epidermis to continue to generate cells that undergo their appendage-specific differentiation (beta stratum formation), when associated with foreign dermis, was examined. Tissue recombination experiments were carried out which placed anterior metatarsal epidermis (scutate scale forming region) from normal 15-day chick embryos with either the anterior metatarsal dermis from 15-day scaleless (sc/sc) embryos or the dermis from the metatarsal footpad (reticulate scale forming region) of 15-day normal embryos. Neither of these dermal tissues are able to induce beta stratum formation in the simple ectodermal epithelium of the chorion, however, the footpad dermis develops an appendage-specific pattern during morphogenesis of the reticulate scales, while the sc/sc dermis does not. Morphological and immunohistological criteria were used to assess appendage-specific epidermal differentiation in these recombinants. The results show that the germinative cell population of the 15-day scutate scale epidermis is committed to generating suprabasal cells that follow their appendage-specific pathways of histogenesis and terminal differentiation. Of significance is the observation that the expression of this determined state occurred only when the epidermis differentiated in association with the footpad dermis, not when it was associated with the sc/sc dermis. The consistent positioning of the newly generated beta strata to the apical regions of individual reticulate-like appendages demonstrates that the dermal cues necessary for terminal epidermal differentiation are present in a reticulate scale pattern. The observation that beta stratum formation is completely missing in the determined scutate scale epidermis when associated with the sc/sc dermis adds to our understanding of the sc/sc defect. The present data support the conclusion of earlier studies that the anterior metatarsal dermis from 15-day sc/sc embryos lacks the ability to induce beta stratum formation in a foreign epithelium. In addition, these observations evoke the hypothesis that the sc/sc dermis either lacks the cues (generated during scutate and reticulate scale morphogenesis) necessary for terminal differentiation of the determined scutate scale epidermis or inhibits the generation of a beta stratum.
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Affiliation(s)
- J Zeltinger
- Department of Biological Sciences, University of South Carolina, Columbia 29208
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20
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Farbman AI, Mbiene JP. Early development and innervation of taste bud-bearing papillae on the rat tongue. J Comp Neurol 1991; 304:172-86. [PMID: 2016415 DOI: 10.1002/cne.903040203] [Citation(s) in RCA: 142] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Early development of fungiform papillae on the fetal rat tongue was examined: (1) to determine whether morphogenesis of the taste bud-bearing fungiform papillae is induced by nerve and (2) to study the growth pattern of the two sensory nerves that innervate the papilla. The papillae first appear on the 15th day of gestation (E15; E1 is the day when the dam is sperm positive) in rows parallel to the midline sulcus. There appears to be a medial-lateral and an anterior-posterior gradient in the sequence of papilla differentiation. The epithelium of the early papilla resembles a multilayered placode topped by a flattened surface periderm. Close examination of the peridermal cells at the apex of the papillae reveals that the cells have fewer surface microvilli and their cytoplasm is more electron opaque than that of similar cells in interpapillary regions. The basal cells in the placode-like epithelium differ from those in interpapillary regions in that they are postmitotic and have more mitochondria. At later stages, the papilla acquires a mesenchymal core and nerves grow into the core. Results from organ culture experiments of tongue fragments taken from E14 fetuses indicate that morphogenesis of fungiform papillae is initiated in the absence of sensory nerve influence, but the nerve exerts a trophic effect on their maintenance. The two sensory nerves of the tongue, the chorda tympani and the lingual branch of the trigeminal nerve, enter the tongue mesenchyme at E14 and grow toward the epithelium. By E15 the chorda tympani branches have reached the developing fungiform papillae, by E16 many have entered the papilla, and by E17 they have penetrated the epithelium at the papilla apex. Their fibers are associated exclusively with the cells at the papilla apex, where the taste bud will develop. The trigeminal nerve ramifies beneath the surface of the entire epithelium by E15. Later, it, too, sends branches into fungiform papillae; these ascend along the trunk of the chorda tympani and at E17 terminate in the connective tissue core around the chorda tympani field. The results are compatible with the notion that the tongue epithelium exerts a general tropic effect on growing axons of both sensory nerves, and the epithelial cells of the fungiform papilla apex exert a similar effect to which only the chorda tympani axons are responsive.
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Affiliation(s)
- A I Farbman
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois 60208-3520
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Shames RB, Jennings AG, Sawyer RH. Expression of the cell adhesion molecules, L-CAM and N-CAM during avian scale development. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1991; 257:195-207. [PMID: 1990052 DOI: 10.1002/jez.1402570208] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
To examine the involvement of cell adhesion molecules in the inductive epithelial-mesenchymal interactions during avian scale development, a study of the spatiotemporal distribution of L-CAM and N-CAM was undertaken. During scutate scale development, L-CAM and N-CAM are expressed together in cells of the transient embryonic layers destined to be lost at hatching. The ongoing linkage of the cells of these layers by both CAMs sets them apart, early in development, as unique cell populations. L-CAM and N-CAM were also expressed simultaneously at the basal surface of the early germinative cells where signal transduction is presumed to occur. In spite of the differences in cell shape, adhesion, density and proliferative state between populations of epidermal placode and interplacode cells, the expression of L-CAM and N-CAM appeared to be uniform and nondiscriminating for these discrete cell lineages. The same pattern of L-CAM and N-CAM expression was observed during morphogenesis of reticulate scales that develop without placode formation. While L-CAM and N-CAM are present during the early stages of scale development and most likely function in cell adhesion, the data do not support a role for these adhesion molecules in the formation of the morphogenetically critical placode and interplacode cell populations. In both scale types, L-CAM became predominantly epithelial, and N-CAM became predominantly dermal as histogenesis occurred. Initially, N-CAM was concentrated near the basal lamina where it may be involved in the reciprocal epidermal-dermal interactions required for morphogenesis. However, as development of the scales progressed, N-CAM disappeared from the tissues. L-CAM expression continued in the epidermis and was intense on all suprabasal cells undergoing differentiation into either an alpha-stratum or beta-stratum. However, L-CAM was more prevalent on the basal cells of alpha-keratinizing regions than on the basal cells of beta-keratinizing regions.
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Affiliation(s)
- R B Shames
- Department of Biological Sciences, University of South Carolina, Columbia 29208
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Sawyer RH. Avian Scale Development XIV: A Study of Cell Proliferation in the Epidermis of the Scaleless, sc/sc, Mutant. (Morphogenesis/skin/cell proliferation/induction). Dev Growth Differ 1990. [DOI: 10.1111/j.1440-169x.1990.00217.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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23
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Tanaka S, Dan K. Study of the Lineage and Cell Cycle of Small Micromeres in Embryos of the Sea Urchin, Hemicentrotus pulcherrimus. (small micromeres/cell cycle/cell lineage/unequal cleavage/sea urchin). Dev Growth Differ 1990. [DOI: 10.1111/j.1440-169x.1990.00145.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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24
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Fukui Y. Cell proliferation in the embryonic quail uropygial gland during placode stage to lumen formation. ANATOMY AND EMBRYOLOGY 1989; 179:347-53. [PMID: 2735529 DOI: 10.1007/bf00305061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The uropygial gland is one of the epidermal derivatives in birds. In the beginning of the morphogenesis of the uropygial gland of the quail embryo, placode formation occurs: Epidermal basal cells remain cuboidal until day 7 of incubation. At day 8 they begin to elongate, become columnar, and develop placode-like structure at day 9. To examine the proliferative activity of the epidermal basal cells, we recorded positions of [3H]-thymidine-labelled nuclei in serial sections by autoradiography (ARG) using a digitizer and a microcomputer. The distribution pattern of labelled nuclei was reconstituted and redisplayed on the cathode ray tube (CRT) as two-dimensional computer graphics. Three-dimensional reconstitution of the same serial sections revealed that cuboidal basal cells in the presumptive uropygial placode became columnar. Unlike the feather and scale placodes, the uropygial placode possessed no resting period of DNA synthesis. The labelling index of the uropygial placode increased considerably compared with that of nonplacode epidermis. No dermal condensation was observed beneath the uropygial placode.
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Affiliation(s)
- Y Fukui
- Department of Biology, Tokyo Women's Medical College, Japan
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Shames RB, Knapp LW, Carver WE, Sawyer RH. Identification, expression, and localization of beta keratin gene products during development of avian scutate scales. Differentiation 1988; 38:115-23. [PMID: 2463202 DOI: 10.1111/j.1432-0436.1988.tb00205.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Epidermal-dermal interactions influence morphogenesis and expression of the beta keratin gene family during development of scales in the embryonic chick. The underlying mechanisms by which these interactions control beta keratin expression are not understood. However, the present study of beta keratin gene expression during avian epidermal differentiation contributes new information with which to investigate the role of tissue interactions in this process. Using beta keratin-specific synthetic oligonucleotide probe, beta keratin mRNA was hybrid-selected from total poly A+ RNA of scutate scales. Seven beta keratin polypeptides were translated in vitro and could be identified by their positions in two-dimensional gels among the detergent-insoluble extracts of scutate scale epidermis. In vivo phosphorylation studies suggested that an additional three beta keratin polypeptides were present as phosphoproteins. The temporal appearance of beta keratin mRNA and the corresponding polypeptides was followed during scutate scale development. Polyclonal antiserum made against two of the beta keratin polypeptides was used for immunohistochemical and immunogold electron-microscopic analysis of beta keratin tissue distribution. Immunological reactivity was observed specifically along the outer scale surface in epidermal cells above the stratum germinativum. Immunogold beads were localized on 3-nm filament bundles. In situ hybridization with a beta keratin-specific RNA probe demonstrated that mRNA accumulated in the same regional manner as the polypeptides. This selective expression of beta keratin genes in specific regions of the developing scutate scale suggests that epidermal-dermal interactions provide not only for morphological events, but also for control of complex patterns of histogenesis and biochemical differentiation.
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Affiliation(s)
- R B Shames
- Department of Biology, University of South Carolina, Columbia 29208
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26
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Nagorcka B, Manoranjan V, Murray J. Complex spatial patterns from tissue interactions—an illustrative model. J Theor Biol 1987. [DOI: 10.1016/s0022-5193(87)80078-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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27
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Carver WE, Sawyer RH. Development and keratinization of the epidermis in the common lizard, Anolis carolinensis. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1987; 243:435-43. [PMID: 2445898 DOI: 10.1002/jez.1402430310] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Epithelial-mesenchymal interactions play important roles in the development of the vertebrate integument with its diverse appendages. As a result of these interactions, specific morphogenetic events occur which result in the formation of distinct epidermal appendages. Following the early morphogenetic events involving cell proliferation and movement, other developmental events such as stratification, histotypic differentiation, and terminal cytodifferentiation occur in the epidermis. Using the common lizard Anolis carolinensis, we are seeking to obtain a better understanding of the relationship between the various developmental events and the expression of alpha and beta keratins, with the aim of eventually understanding the mechanisms by which tissue-specific keratinization patterns are established in the integument. As a first step, we have used immunoblot analyses and indirect immunofluorescence procedures with antisera specific for either alpha or beta keratins to determine the temporal and spatial appearance of these keratins at specific developmental stages. We have found that: 1) There are relatively low molecular weight alpha keratin polypeptides present in the epidermis early in development as morphogenesis is taking place. 2) After morphogenesis occurs and histogenesis is well under way, the alpha keratins which characterize the adult epidermis appear. 3) Only alpha keratins are found in the basal cells of all regions of the epidermis. 4) beta keratins are found only in the suprabasal layers of well-developed scales and show region-specific distribution in overlapping scales.
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Affiliation(s)
- W E Carver
- Department of Biology, University of South Carolina, Columbia 29208
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28
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Westergaard B, Ferguson MWJ. Development of the dentition inAlligator mississippiensis.Later development in the lower jaws of embryos, hatchlings and young juveniles. J Zool (1987) 1987. [DOI: 10.1111/j.1469-7998.1987.tb05984.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Shames RB, Sawyer RH. Expression of beta-keratin genes during development of avian skin appendages. Curr Top Dev Biol 1987; 22:235-53. [PMID: 2443313 DOI: 10.1016/s0070-2153(08)60106-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- R B Shames
- Department of Biology, University of South Carolina, Columbia 29208
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30
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Nagorcka B. The role of a reaction-diffusion system in the initiation of skin organ primordia. I. The first wave of initiation. J Theor Biol 1986. [DOI: 10.1016/s0022-5193(86)80102-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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31
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Shames RB, Sawyer RH. Expression of beta keratin genes during skin development in normal and sc/sc chick embryos. Dev Biol 1986; 116:15-22. [PMID: 2426144 DOI: 10.1016/0012-1606(86)90038-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The expression of RNA sequences specific for scale beta (beta)-keratins has been followed during skin development in normal and scaleless (sc/sc) embryos. Total RNA from skin at various stages (36-46) of development, as well as newly hatched chicks, was immobilized on nitrocellulose paper and hybridized with a [32P]cDNA probe to beta-keratins (pCSK-12). Sequences for beta-keratins showed patterns of expression which were specific for each genotype and scale type examined. During the development of normal scutate scales, which are characterized by the formation of a beta stratum, RNA with beta-keratin sequences first appeared at stage 40, and continued to accumulate through hatching. RNA with beta keratin sequences appeared in scaleless skin between stages 40 and 41, was greatly diminished by stage 44, and was no longer present at stage 46. In normal reticulate scales, which like scaleless skin, do not develop a beta stratum accumulation of RNA with beta-keratin sequences was limited to a brief embryonic period between stages 42 and 44. These patterns of RNA expression correlated well with the appearance of beta-keratin polypeptides, suggesting that beta-keratin synthesis may be controlled at the level of keratin mRNA transcription. Correlations between the patterns of beta-keratin expression and histological events suggest that the brief accumulation of beta-keratin mRNA in scaleless skin and normal reticulate scales is related to the formation of the subperiderm (a protective layer of cells, peculiar to embryonic skin) while the continuous accumulation of beta-keratin mRNA during scutate scale development reflects the formation of a beta stratum.
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32
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Peterson CA, Grainger RM. Differentiation of embryonic chick feather-forming and scale-forming tissues in transfilter cultures. Dev Biol 1985; 111:8-25. [PMID: 2411616 DOI: 10.1016/0012-1606(85)90430-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The dermal-epidermal tissue interaction in the chick embryo, leading to the formation of feathers and scales, provides a good experimental system to study the transfer between tissues of signals which specify cell type. At certain times in development, the dermis controls whether the epidermis forms feathers or scales, each of which are characterized by the synthesis of specific beta-keratins. In our culture system, a dermal effect on epidermal differentiation can still be observed, even when the tissues are separated by a Nuclepore filter, although development is abnormal. Epidermal morphological and histological differentiation in transfilter cultures are distinct and recognizable, more closely resembling feather or scale development, depending on the regional origin of the dermis. Differentiation is more advanced when epidermis is cultured transfilter from scale dermis than from feather dermis, as assessed by morphology and histology, as well as the expression of the tissue-specific gene products, the beta-keratins. Two-dimensional polyacrylamide gel analysis of the beta-keratins reveals that scale dermis cultured transfilter from either presumptive scale or feather epidermis induces the production of 7 of the 9 scale-specific beta-keratins that we have identified. Feather dermis, although less effective in activating the feather gene program when cultured transfilter from either presumptive feather or scale epidermis, is able to turn on the synthesis of 3 to 6 of the 18 feather-specific beta-keratins that we have identified. However, scale epidermis in transfilter recombinants with feather dermis also continues to synthesize many of the scale-specific beta-keratins. Using transmission and scanning electron microscopy, we detect no cell contact between tissues separated by a 0.2-micron pore diameter Nuclepore filter, while 0.4-micron filters readily permit cell processes to traverse the filter. We find that epidermal differentiation is the same with either pore size filter. Furthermore, we do not detect a basement membrane in transfilter cultures, implying that neither direct cell contact between dermis and epidermis, nor a basement membrane between the tissues is required for the extent of epidermal differentiation that we observe.
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33
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Fisher CJ, O'Guin WM, Sawyer RH. Altered keratin biosynthesis follows inhibition of scale morphogenesis by hydrocortisone. Dev Biol 1984; 106:45-52. [PMID: 6208069 DOI: 10.1016/0012-1606(84)90059-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Hydrocortisone, administered onto the chorioallantoic membrane (CAM) of 7- to 10-day-old chick embryos, inhibits scale development, in a dose- and stage-dependent manner. The response is also region specific in that hydrocortisone treatment, at a specific dose and time, will completely block scutellate and interstitial scale development while leaving other scale types unaffected. Using histological, biochemical, and immunofluorescence techniques, we have shown that inhibition of scutellate scale morphogenesis prevents the subsequent formation of a beta stratum and alters expression of the alpha keratins. These data support the hypotheses that each avian scale type has its own distinctive temporal, morphological, and biochemical pattern of development; and in the case of scutellate scale development, hydrocortisone treatment alters keratin biosynthesis by interfering with earlier steps in morphogenesis.
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Dhouailly D, Sawyer RH. Avian scale development. XI. Initial appearance of the dermal defect in scaleless skin. Dev Biol 1984; 105:343-50. [PMID: 6479443 DOI: 10.1016/0012-1606(84)90291-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The chicken mutant, scaleless, is characterized by the total absence of scutate scales. Previous experiments have shown that the scaleless defect is expressed by the epidermal cells while the dermal cells are able to participate in normal scale morphogenesis. However, in association with 14- to 16-day scaleless dermis, normal epidermis or the simple ectoderm of the chorion failed to develop scutate scale epidermis with its characteristic beta stratum. Thus the question arises: since the scaleless dermis starts out functioning normally, when does it become defective? Heterogenetic, heterotopic associations have been performed between 7.5-day to 11.5-day scaleless dermis and a neutral responding tissue, the midventral apteric epidermis, from 10.5-day normal embryos. The results show that up until 9.5 day of incubation the scaleless dermis is able to give instructions for normal scutate scale formation, if combined with normal epidermis. However, after 9.5 days, the scaleless dermis is not able to induce scale formation in normal apteric epidermis. Thus, the functional defect of the scaleless dermis occurs during the time (9 to 10 days of incubation) when epidermal placodes appear in normal embryos. From the present data, at least two explanations are possible. Either the scaleless epidermis is unable to respond to the placode inducing properties being provided by the scaleless dermis and because an epidermal placode does not form the scaleless dermis becomes defective, or the scaleless epidermis does not provide some earlier cue necessary for the scaleless dermis to acquire its placode inducing capabilities.
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Sawyer RH, O'Guin WM, Knapp LW. Avian scale development. X. Dermal induction of tissue-specific keratins in extraembryonic ectoderm. Dev Biol 1984; 101:8-18. [PMID: 6198224 DOI: 10.1016/0012-1606(84)90111-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Epidermal-dermal tissue interactions regulate morphogenesis and tissue-specific keratinization of avian skin appendages. The morphogenesis of scutate scales differs from that of reticulate scales, and the keratin polypeptides of their epidermal surfaces are also different. Do the inductive cues which initiate morphogenesis of these scales also establish the tissue-specific keratin patterns of the epidermis, or does the control of tissue-specific keratinization occur at later stages of development? Unlike feathers, scutate and reticulate scales can be easily separated into their epidermal and dermal components late in development when the major events of morphogenesis have been completed and keratinization will begin. Using a common responding tissue (chorionic epithelium) in combination with scutate and reticulate scale dermises, we find that these embryonic dermises, which have completed morphogeneis, can direct tissue-specific stratification and keratinization. In other words, once a scale dermis has acquired its form, through normal morphogenesis, it is no longer able to initiate morphogenesis of that scale, but it can direct tissue-specific stratification and keratinization of a foreign ectodermal epithelium, which itself has not undergone scale morphogenesis.
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Tanaka S, Kato Y. Epigenesis in developing avian scales. I. Qualitative and quantitative characterization of finite cell populations. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1983; 225:257-69. [PMID: 6833981 DOI: 10.1002/jez.1402250209] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Throughout a period from day 8.5 to day 12.5 of incubation of a chick embryo, a finite cell population of scale epidermis was characterized from various view points such as cellular organization, position, shape, area, number of constituent cells, density, and cell proliferation activity. In this study, the preparation of whole mount specimens was found to be quite valuable. On day 8.5, cells in the prospective scale region could be morphologically distinguished in the tarsometatarsus at a certain distance proximally away from the tarsometatarsal-phalangeal joint. --On day 9.25, about 1,100 cells became highly columnar in shape and densely associated, forming a placode structure. In both distally and proximally adjacent regions of this placode, the cells were semiquadrate in shape and loosely associated, leading to the formation of the interplacode structures. Such contrasting difference in cell organization between placode and interplacode was preserved from day 9.25 to day 11. During this period, both the area and number of constituent cells increased greatly in the placode and only slightly in the interplacode. However, cell proliferation activity was completely suppressed in the placode, and quite active in the interplacode. The activity in cell proliferation proved to be inversely correlated with the density of basal cells. Throughout the present study, it has been demonstrated that the early development of scale epidermis is achieved through a coordinated activity of the two discrete cell populations: the placode and interplacode.
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Tanaka S, Kato Y. Epigenesis in developing avian scales. II. Cell proliferation in relation to morphogenesis and differentiation in the epidermis. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1983; 225:271-83. [PMID: 6833982 DOI: 10.1002/jez.1402250210] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Throughout the early development of chicken scale epidermis, consisting of discrete placode and interplacode cell populations, morphogenesis and differentiation were examined from the standpoints of cell proliferation. From day 9.25 to day 11, active cell proliferation was observed only in the interplacode region, whereas the number of constituent cells increased considerably within the placode. After 26 hr of continuous labeling with [3H]thymidine (3H-TdR) in ovo, three regions could be recognized: (1) unlabeled placode on the distal edge, (2) labeled placode in both lateral and proximal sites to the unlabeled placode, and (3) extensively labeled interplacode on the most proximal site of the scale. Examination of the distribution pattern of labeled cells has demonstrated that a fraction of the cells in the interplacode transits and annexes only to the proximal side of the placode. Cells transit after mitosis, accompanied with changes in morphology and proliferation activity. During the period of cell transition, orientation of mitosis paralleled completely along the proximodistal axis of the scale. Cell marking with carbon particles was carried in organ cultures from day 10, and the changes in the position of marked cells were observed. The results confirm those obtained after continuous labeling with 3H-TdR. Various combinations of pulse-chase experiments with 3H-TdR clearly demonstrated the establishment of a cell lineage in which cells were aligned along the axis of the scale according to order of their birth. Along with a sudden resumption of active proliferation after day 11, a new class of cells (suprabasal cells) differentiated upward from the basal cells on the top region of the hump scale. At the first stage of development of suprabasal cells from day 11 to day 11.75, the direction of mitoses became preferentially polarized in the direction of axis vertical to the basal lamina. The important coordination of cell proliferation in relation to morphogenesis and cell differentiation is discussed.
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Tanaka S. Changes in morphology and cell proliferation during vitamin A-induced mucous metaplasia of developing chick scale cultured in vitro. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1982; 223:139-54. [PMID: 7142942 DOI: 10.1002/jez.1402230206] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Throughout the process of vitamin A (V-A)-induced mucous metaplasia of the scale epidermis of a 12-day chick embryo, changes in the activities of cell proliferation were investigated in reference to morphological changes. In both the control and V-A cultures after 5 days, a dynamic steady state was established among the stratified layers which differentiated into keratinizing epidermis during the first 7 days. In the control, cell proliferates within only the basal layer and the cell cycle time, except Tg2, increased during 30 days of culture. In the V-A culture, this tendency was reversed in each parameter between day 10 and day 13, when symptoms of mucous metaplasia became morphologically prominent. On day 13 in the V-A culture, superficial cornified cell layers were sloughed off as whole sheets and concurrently DNA synthesis was reactivated throughout the entire cell layers of the epithelium. The correlation between two of five cell cycle times (Tgc, Tg1, Ts, Tg2, Tm) was statistically treated as linear regression lines and gave highly significant coefficients in every case. The regression coefficients between Ts and Tgc and Ts and Tg1 in V-A culture are significantly (P less than 0.01) smaller than those in the control. It was found that V-A induced sequential alterations in mucous metaplasia with respect both to morphology and proliferation in the epidermis of the chick embryo.
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McAleese SR, Sawyer RH. Avian scale development. IX. Scale formation by scaleless (sc/sc) epidermis under the influence of normal scale dermis. Dev Biol 1982; 89:493-502. [PMID: 6173278 DOI: 10.1016/0012-1606(82)90337-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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40
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O'Guin WM, Sawyer RH. Avian scale development. VII. Relationships between morphogenetic and biosynthetic differentiation. Dev Biol 1982; 89:485-92. [PMID: 6173277 DOI: 10.1016/0012-1606(82)90336-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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41
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McAleese SR, Sawyer RH. Correcting the phenotype of the epidermis from chick embryos homozygous for the gene scaleless (sc/sc). Science 1981; 214:1033-4. [PMID: 7029712 DOI: 10.1126/science.7029712] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Scutate scales are completely missing in the scaleless (sc/sc) mutant chicken. Organ cultures consisting of epidermis from sc/sc embryos combined with normal (+/+) scale dermis of the same developmental age produce the scaleless phenotype, but the same scaleless epidermis in combination with normal dermis from more differentiated embryonic scales forms perfectly normal scales.
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42
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Sawyer RH, Borg TK. Avian scale development. VII. Normal keratinization follows abnormal morphogenesis of reticulate scales from the “scaleless” mutant. J Morphol 1980; 166:197-202. [DOI: 10.1002/jmor.1051660206] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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43
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Sawyer RH, Borg TK. Avian scale development. VI. Ultrastructure of the keratinizing cells of reticulate scales. J Morphol 1979; 161:111-121. [DOI: 10.1002/jmor.1051610107] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Mirkes PE, Sawyer RH. Abnormal scale morphogenesis: relationship of polypeptide patterns to action of the scaleless gene. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1979; 208:195-200. [PMID: 469483 DOI: 10.1002/jez.1402080207] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The polyacrylamide gradient gel electrophoresis (PAGGE) pattern of polypeptides isolated from normal scuttate scale epidermis of 1-week-old chicks was different from that of the anterior shank epidermis from 1-week-old scaleless mutant chicks. The PAGGE patterns of polypeptides isolated from normal and scaleless reticulate scale epidermis (from 1-week-old chicks) differed by only one band, whereas comparison of mutant's scuttate and reticulate patterns showed three band differences. These data are discussed in relation to the action of the scaleless gene on early morphogenesis of the two types of scales.
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Fisher C, Sawyer RH. Response of the avian chorionic epithelium to presumptive scale-forming dermis. ACTA ACUST UNITED AC 1979. [DOI: 10.1002/jez.1402070319] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Sawyer RH. Keratogenic metaplasia of the avian chorionic epithelium: Absence of the Beta stratum which characterizes the epidermis of the avian scutellate scale. ACTA ACUST UNITED AC 1978. [DOI: 10.1002/jez.1402050207] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Sawyer RH, Craig KF. Avian scale development. Absence of an "epidermal placode" in reticulate scale morphogenesis. J Morphol 1977; 154:83-93. [PMID: 915950 DOI: 10.1002/jmor.1051540106] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Timed-sequence studies have shown that reticulate scales on the ventral footpads of birds do not undergo "epidermal placode" formation during their morphogenesis, but arise as symmetrical evaluations similar to the scales of snakes and lizards. Unlike the scutellate scales on the dorsal surface of the foot, in which the formation of an "epidermal placode" and its subsequent morphogenesis result in disticnt outer and inner epidermal surfaces, the reticulate scales elaborate only one type of epidermal surface.
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Nuttall RP. DNA synthesis during the development of the chick cornea. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1976; 198:193-208. [PMID: 978170 DOI: 10.1002/jez.1401980209] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The frequency and pattern of DNA synthesis were analysed autoradiographically in the developing chick cornea. Each cellular population was studied in time-sequence fashion from the time of its appearance until hatching. There is a sharp drop in the synthetic index (number of labeled cells/total number of cells) in the anterior corneal epithelium soon after its formation, corresponding in time to the secretion of extracellular matrix material by this tissue. A similar decrease does not occur in adjacent tissues. Continous labeling experiments show that about 20% of the corneal cells are not in the proliferative pool at this time while 100% of the cells in the underlying lens epithelium and the surrounding head epidermis and head mesenchyme are labeled. Cell cycle measurements indicate that the proliferative kinetics of both the corneal epithelium and the head epidermis are similar at this time even though the percentage of labeled cells in each region differs. The formation of the corneal endothelium and the movement of fibroblasts into the stromal region are events which involve extensive cellular migration. Labeled cells are observed at all stages of both endothelial and stromal fibroblast migration, indicating that DNA synthesis occurs during the course of cellular migration in the developing cornea.
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