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Involucrin
Involucrin is a protein component of human skin and in humans is encoded by the ''IVL'' gene. In binding the protein loricrin, involucrin contributes to the formation of a cell envelope that protects corneocytes in the skin. Gene This gene is mapped to 1q21, among calpactin I light chain, trichohyalin, profillaggrin, loricrin, and calcyclin. Function Involucrin is a highly reactive, soluble, transglutaminase substrate protein present in keratinocytes of epidermis and other stratified squamous epithelia. It first appears in the cell cytosol, but ultimately becomes cross-linked to membrane proteins by transglutaminase thus helping in the formation of an insoluble envelope beneath the plasma membrane functioning as a glutamyl donor during assembly of the cornified envelope. Involucrin is synthesised in the stratum spinosum and cross linked in the stratum granulosum by the transglutaminase enzyme that makes it highly stable. Thus it provides structural support to the cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TCHH
Trichohyalin is a protein that in mammals is encoded by the ''TCHH'' gene. Discovery In 1903 the name ''trichohyalin'' was assigned to the granules of the inner root sheath (IRS) of hair follicles discovered by Hans Vörner. In 1986 the name was reassigned to a protein isolated from sheep wool follicles. Gene location The human TCHH is located on the long (q) arm of chromosome 1 at region 2 band 1 sub-band 3 (1q21.3), from base pair 152,105,403 to base pair 152,116,368map. This region in chromosome 1q21 is known as the epidermal differentiation complex, since it harbors over fifty other genes involved in keratinocyte differentiation. Gene coding sequence contains 5829 nucleotides. Gene orthologs were identified in most mammals including mice, chickens, rats, pigs, sheep, horses and other species. Protein localisation Trichohyalin is highly expressed in the inner root sheath cells of the hair follicle and medulla. It was also detected in the granular layer and stratum corne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corneocyte
Corneocytes are terminally differentiated keratinocytes and compose most of the stratum corneum, the outermost layer of the epidermis. They are regularly replaced through desquamation and renewal from lower epidermal layers and are essential for its function as a skin barrier. Structure Corneocytes are keratinocytes without nuclei and cytoplasmic organelles. They contain a highly insoluble cornified envelope within the plasma membrane, and lipids (fatty acids, sterols and ceramides) released from lamellar bodies within the epidermis. The corneocytes are interlocked with each other and organized as vertical columns of 10–30 cells to form the stratum corneum. Corneocytes in the lower part of the stratum corneum are bridged together through specialized junctions ( corneodesmosomes). Those junctions disintegrate as corneocytes migrate toward the surface of the skin and result in desquamation. At the same time, as those loosened junctions encounter more hydration, they will expan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loricrin
Loricrin is a protein that in humans is encoded by the ''LOR'' gene. Function Loricrin is a major protein component of the stratum corneum, cornified cell envelope found in terminally differentiated epidermis (skin), epidermal cells. Loricrin is expressed in the granular layer of all keratinized epithelial cells of mammals tested including oral, esophageal and stomach mucosa of rodents, tracheal squamous metaplasia of vitamin A deficient hamster and estrogen induced squamous vaginal epithelium of rats. Clinical significance Mutations in the LOR gene are associated with Vohwinkel's syndrome and Camisa disease, both inherited skin diseases. See also * List of cutaneous conditions caused by mutations in keratins References Further reading * * * * * * * * * * * * * * * * * {{gene-1-stub Structural proteins Cytoskeleton Skin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corneocyte
Corneocytes are terminally differentiated keratinocytes and compose most of the stratum corneum, the outermost layer of the epidermis. They are regularly replaced through desquamation and renewal from lower epidermal layers and are essential for its function as a skin barrier. Structure Corneocytes are keratinocytes without nuclei and cytoplasmic organelles. They contain a highly insoluble cornified envelope within the plasma membrane, and lipids (fatty acids, sterols and ceramides) released from lamellar bodies within the epidermis. The corneocytes are interlocked with each other and organized as vertical columns of 10–30 cells to form the stratum corneum. Corneocytes in the lower part of the stratum corneum are bridged together through specialized junctions ( corneodesmosomes). Those junctions disintegrate as corneocytes migrate toward the surface of the skin and result in desquamation. At the same time, as those loosened junctions encounter more hydration, they will expan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratinocytes
Keratinocytes are the primary type of cell found in the epidermis, the outermost layer of the skin. In humans, they constitute 90% of epidermal skin cells. Basal cells in the basal layer (''stratum basale'') of the skin are sometimes referred to as basal keratinocytes. Keratinocytes form a barrier against environmental damage by heat, UV radiation, water loss, pathogenic bacteria, fungi, parasites, and viruses. A number of structural proteins, enzymes, lipids, and antimicrobial peptides contribute to maintain the important barrier function of the skin. Keratinocytes differentiate from epidermal stem cells in the lower part of the epidermis and migrate towards the surface, finally becoming corneocytes and eventually be shed off, which happens every 40 to 56 days in humans. Function The primary function of keratinocytes is the formation of a barrier against environmental damage by heat, UV radiation, water loss, pathogenic bacteria, fungi, parasites, and viruses. Pathogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flavanoid
Flavonoids (or bioflavonoids; from the Latin word ''flavus'', meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans. Chemically, flavonoids have the general structure of a 15-carbon skeleton, which consists of two phenyl rings (A and B) and a heterocyclic ring (C, the ring containing the embedded oxygen). This carbon structure can be abbreviated C6-C3-C6. According to the IUPAC nomenclature, they can be classified into: *flavonoids or bioflavonoids *isoflavonoids, derived from 3-phenyl chromen-4-one (3-phenyl-1,4-benzopyrone) structure *neoflavonoids, derived from 4-phenylcoumarine (4-phenyl-1,2-benzopyrone) structure The three flavonoid classes above are all ketone-containing compounds and as such, anthoxanthins (flavones and flavonols). This class was the first to be termed bioflavonoids. The terms flavonoid and bioflavonoid have also been more loosely used to describe non-k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
