Peridermal granules of the chick embryo. Histochemical, ultrastructural and immuno-electron microscopical study.

Abstract

ITO, T. and MORI, T. Peridermal Granules of the Chick Embryo : Histochemical, Ultrastructural and Immuno-Electron Miroscopical Study. Tohoku J. exp. Med., 1987, 151(2), [169][170][171][172][173][174][175][176][177][178][179][180] In the chick embryo, the periderm covering certain derivatives of the integumentum, such as the beak, the scale and the claw, grows thick and contains specific cytoplasmic granules. In this report, we present the histochemical properties and the fine structures of these peridermal granules especially over the egg tooth region of the upper beak. The granules were brilliantly stained with acid dyes. A positive reaction for tyrosine and arginine suggested that this acidophilia was due to a certain basic protein. Although the reaction of DDD to SH and SS groups was moderate, a presence of keratin was strongly suggested immunohistochemically by using the rabbit anti-keratin antiserum. There also existed a possibility of some compound lipids. Under an electron microscope, these granules were found to consist of anastomosing ribbons which were less than 60 nm in width and were stained with rabbit anti-keratin antiserum. peridermal granules ; chick embryo ; histochemical property ; fine structure ; immunoelectron microscopic study The presence of acidophilic granules in the periderm has been known in the integumentum of sauropsid embryo (Rose 1892; Rosenstadt 1897). In the chick embryo, Branca (1907) described that these granules were found in the periderm especially over the intensely keratinizing regions of the skin such as the beak, the scale and the claw.These peridermal granules have attracted the notice of some researchers in relation to keratinization.For example, Voigt and Fusenig (1979) reported that they were a type of keratohyaline granules. In this report, the histochemical properties and the fine structures of these granules are presented, and the periderm covering the upper beak of the chick embryo is examined ultrastructurally immediately before hatching. In addition, the possibile relation of the peridermal granules to the differentiatiom of the epidermis is also discussed.

The Trichohyalin-Like Protein Scaffoldin Is Expressed in the Multilayered Periderm during Development of Avian Beak and Egg Tooth

“…In the chicken, SCFN was detected in the multilayered periderm around the egg tooth ( Figure 5D,E). It formed granules that corresponded in size and distribution to eosinophilic periderm granules [38] (Figure 5A-C), supporting the conclusion of a previous study that identified SCFN as a major component of granules in the periderm covering the embryonic epidermis [39]. A similar distribution of eosinophilic periderm granules (Figure 6A,B) and accumulation of SCFN were observed on the upper embryonic beak of quails ( Figure 6E,F).…”

Immunolocalization of epidermal differentiation complex proteins reveals distinct molecular compositions of cells that control structure and mechanical properties of avian skin appendages

“…In particular, diverse proteins contribute effects on the final biomechanical properties of different parts of feathers. It also remains to be clarified whether all or only some of the proteins of downfeathers are also present in the adult feather follicle during the initial phase of their regeneration, when periderm granules are present like in embryonic skin (Alibardi & Toni, 2008; Ito & Mori, 1987; Kuraitis & Bowers, 1978). These minor proteins may contribute to the mechanical resistance and flexibility of adult barbules or to the higher rigidity of the calamus and rachis.…”

Microscopic and immunohistochemical study on the cornification of the developing beak in the turtle Emydura macquarii

“…Similar embryonic organelles in birds, the periderm granules, contain some acidic keratins and a trichohyaline‐like protein indicated as “scaffoldin” (Ito and Mori, ; Militz et al, 2013; Alibardi, ; Alibardi et al, 2015). Coarse filaments aggregate into reticulate bodies, resembling/corresponding to periderm granules of birds (Kuraitis and Brumbaugh, ; Sawyer et al, ; Alibardi, , 2009b,c, 2014b).…”