![]() ![]() Cytokeratins (CKs) along with microfilaments and microtubules form this framework. These epithelial cells are composed of a cytoskeleton which forms a structural framework of the cell. It is estimated as 52–75 days in the skin, 4–14 days in the gut, 41–75 days in the gingiva and 25 days in the cheek. The time taken by a cell to divide and pass through the entire epithelium is called turnover time. This process of migration of an epithelial cell from the basal cell layer to the surface is called maturation. After reaching the surface, it is shed off, a process called desquamation. At the end of the differentiation process, a dead cell filled with densely packed protein contained within a toughened cell membrane is formed. Once it enters the maturing compartment, the keratinocyte undergoes differentiation and becomes committed to biochemical and morphologic changes. After each cell division, the daughter cell either enters the progenitor population again or enters the maturing compartment. The progenitor population consists of stem cells and amplifying cells. There are two types of cell populations: progenitor population and maturing population. This process of maturation follows two patterns: keratinization and nonkeratinization. These cells undergo a process of maturation during which the cells produced by the mitotic division in the basal layer migrate to the surface where they are shed off and are replaced by the maturing cell population. The oral epithelium is stratified squamous type consisting of cells called keratinocytes. Domains and subdomains are determined by the amino acid sequence of the keratin and serve various functions in the assembly of keratin filaments and in the binding of keratins and keratin filaments to cell adhesion complexes or to signaling molecules. Each of these three domains is divided into subdomains. The secondary structure of keratins is also divided into three parts, i.e., the head domain (toward the N-terminal of the molecule), the rod domain in the center and the tail domain. 1984).Īll proteins that form intermediate filaments have a tripartite secondary structure consisting of an N-terminal head domain, a central α - helical rod domain and C-terminal tail domain, and all proteins can self-assemble into filaments. The amino acid sequence of a keratin influences the properties and functions of the keratin filament (Roop et al. The review describes the physiology of keratinization, pathology behind abnormal keratin formation and various keratin disorders.Įach keratin is characterized by a chain of amino acids as the primary structure of the keratin protein, which may vary in the number and sequence of amino acids, as well as in polarity, charge and size (Brown, 1950 Makar et al. This review article discusses the classification, structure, functions, the stains used for the demonstration of keratin and associated pathology. These keratins and keratin-associated proteins have become important markers in diagnostic pathology. In addition, there are a number of disorders which are seen because of abnormal keratinization. Mutations in the genes which regulate the expression of keratin proteins are associated with a number of disorders which show defects in both skin and mucosa. They are expressed in a specific pattern and according to the stage of cellular differentiation. The word keratin covers these intermediate filament-forming proteins within the keratinocytes. These intermediate filaments maintain the structural integrity of the keratinocytes. Trending Questions Is the statement true that unlike planets a dwarf planet cannot have moons? Is this the answer the moon unlike the earth does not rotate so you see the same side of the moon? Why is Light Year used instead of kilometers? Why does the sky appear much bluer in some states? Can a spore be seen with the naked eye? Who sings so far away? Why is the heliocentric picture of the solar system called a model of the solar system? What model of the universe that suggests that the sun is the center of the universe was first brought by? What other planets in the solar system have wind? How are lunar and sonar eclipse different and alike? What are three ways that the inner planets are different from the putter planets? What is the smallest piece of a chemical element called? How high up does the troposphere go? Which planet has the lowest inclination to the ecliptic of any planet? A photograph showing circular star trails is evidence that the earth? What units are distances to stars measured in and why? What is the relationship between Vega and Pleiades? Two stars having annual parallax of 0.1 and 0.02 arc seconds respectively.If they appear to have same magnitude.Cytoskeleton of a cell is made up of microfilaments, microtubules and intermediate filaments. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |