The dermal side of the chick embryonic skin was observed by scanning electron microscopy (SEM) after the removal of dermal components. Epidermis free of dermis was prepared as follows: Tissues were fixed, hydrolyzed with hydrochloric acid (HC1), digested with collagenase or trypsin, and processed for SEM observation. The epidermis from the anterior tarsometatarsus and the foot pad was examined....

The lipide composition of epidermis and dermis under the influence of the hair growth cycle and following the topical application of methylcholanthrene was inves tigated. The percentage of cholesterol and phospholipide was lowest in anagen and telogen epidermis, was nearly doubled in early and late hyperplastic epidermis, and rose to even higher values in squamous-cell carcinomas. The cholester...

The root epidermis of Arabidopsis provides an exceptional model for studying the molecular basis of cell fate and differentiation. To obtain a systems-level view of root epidermal cell differentiation, we used a genome-wide transcriptome approach to define and organize a large set of genes into a transcriptional regulatory network. Using cell fate mutants that produce only one of the two epider...

The alpha 6/beta 4 complex is a member of the integrin family of adhesion receptors. It is found on a variety of epithelial cell types, but is most strongly expressed on stratified squamous epithelia. Fluorescent antibody staining of human epidermis suggests that the beta 4 subunit is strongly localized to the basal region showing a similar distribution to that of the 230-kD bullous pemphigoid ...

The structure and development of ommatidia has been examined in Oncopeltus fasciatus (Lygaeidae). Each ommatidium is composed of 18 cells comprising four crystalline cone cells, two primary pigment cells, four secondary pigment cells and eight retinula cells. Ommatidia are of the apposition type and the retinula cells are arranged on the open rhabdomere plan. During the five larval stages the r...

Eccrine sweat glands are generally considered to be a possible epidermal stem cell source. Here we compared the multilayered epithelia formed by epidermal keratinocytes and those formed by eccrine sweat gland cells. We demonstrated both in vitro and in vivo the capability of human eccrine sweat gland cells to form a stratified interfollicular epidermis substitute on collagen hydrogels. This is ...

BACKGROUND The multifunctional receptor LRP1 has been shown to bind and internalize a large number of protein ligands with biological importance such as the pan-protease inhibitor alpha2-macroglobulin (alpha2M). We recently identified Alpha2ML1, a new member of the alpha2M gene family, expressed in epidermis. alpha2ML1 might contribute to the regulation of desquamation through its inhibitory ac...

Cabbage belonging to Brassicaceae family is one of the most important vegetables cultivated worldwide. The economically important part of cabbage crop is head, formed by leaves which may be of splitting and non-splitting types. Cabbage varieties showing head splitting causes huge loss to the farmers and therefore finding the molecular and structural basis of splitting types would be helpful to ...

We use a new cell marker to study cell lineage of the epidermis, oenocytes and ventral muscles in the Drosophila abdomen. We find that while the epidermal cells and the oenocytes share common precursors until late in development, the muscles derive from a separate lineage. Marked clones in the muscles, but not in the epidermis and oenocytes, can occasionally extend between neighbouring segments...

When the anteroposterior axis of a cockroach leg is reversed at a graft by exchanging a left leg for a right leg at the mid-tibia level, regeneration occurs in the region of the graft/host junction. This results in the formation of a pair of lateral supernumerary legs. In these experiments the patterns of cell division which take place during supernumerary leg formation were observed in section...