The initial expression and patterned appearance of tenascin in scutate scales is absent from the dermis of the scaleless ( sc/sc) chicken

• Published in: Developmental biology Vol. 147; no. 1; pp. 174 - 186
• Main Authors: Shames, Rose B., Jennings, Anita G., Sawyer, Roger H.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.09.1991
• Subjects: Animals; Antibodies, Monoclonal; Cell Adhesion; Cell Adhesion Molecules - analysis; Cell Adhesion Molecules, Neuronal - analysis; Cell Adhesion Molecules, Neuronal - biosynthesis; Chick Embryo; Embryonic and Fetal Development; Extracellular Matrix Proteins - analysis; Extracellular Matrix Proteins - biosynthesis; Fluorescent Antibody Technique; Morphogenesis; Muscle Development; Mutation; Skin - cytology; Skin - embryology; Tenascin
• ISSN: 0012-1606; 1095-564X
• DOI: 10.1016/S0012-1606(05)80016-8

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 β stratum, with its unique β keratins, characterizes the epidermis of the outer surface, while the epidermis of the inner surface elaborates an α 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 β and α 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.