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Keratin 16
Keratin 16 is a protein that in humans is encoded by the ''KRT16'' gene. Keratin 16 is a type I cytokeratin. It is paired with keratin 6 in a number of epithelial tissues, including nail bed, esophagus, tongue, and hair follicles. Mutations in the gene encoding this protein are associated with the genetic skin disorders including pachyonychia congenita, non-epidermolytic palmoplantar keratoderma and unilateral palmoplantar verrucous nevus A Unilateral palmoplantar verrucous nevus is a cutaneous condition that has features of pachyonychia congenita. See also * Unilateral nevoid telangiectasia * List of cutaneous conditions Many skin conditions affect the human integumenta .... References External links GeneReviews/NCBI/NIH/UW entry on Pachyonychia Congenita Further reading * * * * * * * * * * * * * * * * * * Keratins {{Gene-17-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type I Cytokeratin
Type I keratins (or Type I cytokeratins) are cytokeratins that constitute the Type I intermediate filaments (IFs) of the intracytoplasmatic cytoskeleton, which is present in all mammalian epithelial cells. Most of the type I keratins consist of acidic, low molecular weight proteins which in vivo are arranged in pairs of heterotypic Type I and Type II keratin chains, coexpressed during differentiation of simple and stratified epithelial tissues. Type I keratins are encoded on chromosome 17q and encompasses: K9, K10, K11, K12, K13, K14, K15, K16, K17, K18, K19 and K20. Their molecular weight ranges from 40 kDa (K19) to 64 kDa (K9). See also *Type II keratin Type II keratins (or Type II cytokeratins) constitutes the Type II intermediate filaments (IFs) of the intracytoplasmatic cytoskeleton, which is present in all mammalian epithelial cells. The type 2 cytokeratins consist of basic or neutral, high mol ... External links * Proteopedia page on keratins Keratins {{Fibrous prote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratin 6
Keratin 6A is one of the 27 different type II keratins expressed in humans. Keratin 6A was the first type II keratin sequence determined. Analysis of the sequence of this keratin together with that of the first type I keratin led to the discovery of the four helical domains in the central rod of keratins. In humans Keratin 6A is encoded by the ''KRT6A'' gene. Keratins Keratins are the intermediate filament proteins that form a dense meshwork of filaments throughout the cytoplasm of epithelial cells. Keratins form heteropolymers consisting of a type I and a type II keratin. Keratins are generally expressed in particular pairs of type I and type II keratin proteins in a tissue-specific and cellular differentiation-specific manner. The keratin proteins of epithelial tissues are commonly known as "keratins" or are sometimes referred to as "epithelial keratins" or "cytokeratins". The specialized keratins of hair and nail are known as "hard keratins" or " trichocyte keratins". Tric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epithelial Tissue
Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercellular matrix. Epithelial tissues line the outer surfaces of organs and blood vessels throughout the body, as well as the inner surfaces of cavities in many internal organs. An example is the epidermis, the outermost layer of the skin. There are three principal shapes of epithelial cell: squamous (scaly), columnar, and cuboidal. These can be arranged in a singular layer of cells as simple epithelium, either squamous, columnar, or cuboidal, or in layers of two or more cells deep as stratified (layered), or ''compound'', either squamous, columnar or cuboidal. In some tissues, a layer of columnar cells may appear to be stratified due to the placement of the nuclei. This sort of tissue is called pseudostratified. All glands are made up of epith ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esophagus
The esophagus (American English) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the stomach. The esophagus is a fibromuscular tube, about long in adults, that travels behind the trachea and heart, passes through the diaphragm, and empties into the uppermost region of the stomach. During swallowing, the epiglottis tilts backwards to prevent food from going down the larynx and lungs. The word ''oesophagus'' is from Ancient Greek οἰσοφάγος (oisophágos), from οἴσω (oísō), future form of φέρω (phérō, “I carry”) + ἔφαγον (éphagon, “I ate”). The wall of the esophagus from the lumen outwards consists of mucosa, submucosa (connective tissue), layers of muscle fibers between layers of fibrous tissue, and an outer layer of connective tissue. The mucosa is a stratified squamous epithel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tongue
The tongue is a muscular organ (anatomy), organ in the mouth of a typical tetrapod. It manipulates food for mastication and swallowing as part of the digestive system, digestive process, and is the primary organ of taste. The tongue's upper surface (dorsum) is covered by taste buds housed in numerous lingual papillae. It is sensitive and kept moist by saliva and is richly supplied with nerves and blood vessels. The tongue also serves as a natural means of oral hygiene, cleaning the teeth. A major function of the tongue is the enabling of speech in humans and animal communication, vocalization in other animals. The human tongue is divided into two parts, an oral cavity, oral part at the front and a pharynx, pharyngeal part at the back. The left and right sides are also separated along most of its length by a vertical section of connective tissue, fibrous tissue (the lingual septum) that results in a groove, the median sulcus, on the tongue's surface. There are two groups of muscle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hair Follicle
The hair follicle is an organ found in mammalian skin. It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions. The hair follicle regulates hair growth via a complex interaction between hormones, neuropeptides, and immune cells. This complex interaction induces the hair follicle to produce different types of hair as seen on different parts of the body. For example, terminal hairs grow on the scalp and lanugo hairs are seen covering the bodies of fetuses in the uterus and in some newborn babies. The process of hair growth occurs in distinct sequential stages. The first stage is called ''anagen'' and is the active growth phase, ''telogen'' is the resting stage, ''catagen'' is the regression of the hair follicle phase, ''exogen'' is the active shedding of hair phase and lastly ''kenogen'' is the phase between the empty hair follicle and the growth of new hair. The function of hair in humans has long been a subject of interest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachyonychia Congenita
Pachyonychia congenita (often abbreviated as "PC") is a rare group of autosomal dominant skin disorders that are caused by a mutation in one of five different keratin genes. Pachyonychia congenita is often associated with thickened toenails, plantar keratoderma, and plantar pain. Signs and symptoms Pachyonychia congenita is characterized by a clinical triad present in 97% of people with PC by the time they turn 10 years old: # Thickened toenails # Plantar keratoderma # Plantar pain that may require some patients to use wheelchairs, canes, crutches, and pain medications due to its severity Other signs and symptoms found in PC include: * Thickened fingernails * Palmar keratoderma * Oral leukokeratosis * Cysts, including steatocystoma multiplex * Follicular hyperkeratosis * Natal or prenatal teeth * Blisters * Excessive sweating of the palms and soles * Excess earwax production * Ear pain * Hoarseness * Angular chelitis * Fingernail and toenail infections Cause The conditio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-epidermolytic Palmoplantar Keratoderma
Palmoplantar keratodermas are a heterogeneous group of disorders characterized by abnormal thickening of the stratum corneum of the palms and soles. Autosomal recessive, dominant, X-linked, and acquired forms have all been described. Types Clinically, three distinct patterns of palmoplantar keratoderma may be identified: diffuse, focal, and punctate. Diffuse Diffuse palmoplantar keratoderma is a type of palmoplantar keratoderma that is characterized by an even, thick, symmetric hyperkeratosis over the whole of the palm and sole, usually evident at birth or in the first few months of life. Restated, diffuse palmoplantar keratoderma is an autosomal dominant disorder in which hyperkeratosis is confined to the palms and soles. The two major types can have a similar clinical appearance: *''Diffuse epidermolytic palmoplantar keratoderma'' (also known as "Palmoplantar keratoderma cum degeneratione granulosa Vörner," "Vörner's epidermolytic palmoplantar keratoderma", and "Vörn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unilateral Palmoplantar Verrucous Nevus
A Unilateral palmoplantar verrucous nevus is a cutaneous condition that has features of pachyonychia congenita. See also * Unilateral nevoid telangiectasia * List of cutaneous conditions Many skin conditions affect the human integumentary system—the organ system covering the entire surface of the body and composed of skin, hair, nails, and related muscle and glands. The major function of this system is as a barrier against t ... References Epidermal nevi, neoplasms, and cysts {{Epidermal-growth-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
