Caleb Freeman1; Sidharth Sonthalia2. Introduction The epidermis is comprised of 4 or 5 layers, depending on the location of the skin sampled. These layers from deep to superficial are stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum. The stratum lucidum is typically only present in the thick skin found in areas such as the palm or soles.
|Published (Last):||22 July 2016|
|PDF File Size:||2.27 Mb|
|ePub File Size:||8.4 Mb|
|Price:||Free* [*Free Regsitration Required]|
The chemical nature of keratohyalin was widely studied by histochemical methods. Positive reactions were seen for protein-bound histidine Reaven and Cox ; Nagy-Vezekenyi , metal-binding proteins Pizzo-lato and Lillie , RNA-like and carbohydrate moieties Singh et al. However the choice of method determines the histochemical or immunohistochemical demonstration of certain components, and a negative reaction observed by one technique does not exclude the possibility that a component is present in the granules.
For instance, a cysteine-rich protein in keratohyalin granules, not detected by early histochemical study, was later shown to be present by improved cytochemistry Jessen ; Tezuka et al. The chemical nature of keratohyalin was also examined more directly by biochemical analysis of isolated granules or extracts made from granular and cornified cells. It is now generally accepted that keratohyalin granules in the epidermis are formed in differentiating cells by aggregation of keratohyalin with tonofilaments and other constituents without being surrounded by a membrane and that during formation of cornified cells keratohyalin is dispersed in the interfilamentous spaces.
In this paper we discuss different proteins classified as keratohyalin, their synthesis and metabolism, and nucleic acids which may play a role in keratohyalin formation. This process is experimental and the keywords may be updated as the learning algorithm improves. This is a preview of subscription content, log in to check access. Preview Unable to display preview. Download preview PDF. J Biol Chem — PubMed Google Scholar Balmain A The synthesis of specific proteins in adult mouse epidermis during phases of proliferation and differentiation induced by the tumor promoter TPA, and in basal and differentiating layers of neonatal mouse epidermis.
Biosynthesis of histidine-rich and cystine-rich proteins in vitro and in vivo. Isolation and purification of histidine-rich protein of the newborn rat.
Science — PubMed CrossRef Google Scholar Ugel AR Studies on isolated aggregating oligoribonucleoproteins of the epidermis with histochemical and morphological characteristics of keratohyalin.