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Keratin 9
Keratin 9 is a protein that in humans is encoded by the ''KRT9'' gene. Keratin 9 is a type I cytokeratin. It is found only in the terminally differentiated epidermis of palms and soles. Mutations in the gene encoding this protein cause epidermolytic palmoplantar keratoderma Epidermolytic ichthyosis (EI), also known as bullous epidermis ichthyosis (BEI), epidermolytic hyperkeratosis (EHK), bullous congenital ichthyosiform erythroderma (BCIE), bullous ichthyosiform erythrodermaFreedberg, et al. (2003). ''Fitzpatrick' .... References 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] |
Epidermis (skin)
The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and hypodermis. The epidermis layer provides a barrier to infection from environmental pathogens and regulates the amount of water released from the body into the atmosphere through transepidermal water loss. The epidermis is composed of multiple layers of flattened cells that overlie a base layer (stratum basale) composed of columnar cells arranged perpendicularly. The layers of cells develop from stem cells in the basal layer. The human epidermis is a familiar example of epithelium, particularly a stratified squamous epithelium. The word epidermis is derived through Latin , itself and . Something related to or part of the epidermis is termed epidermal. Structure Cellular components The epidermis primarily consists of keratinocytes ( proliferating basal and differentiated suprabasal), which comprise 90% of its cells, but also contains melanocytes, Langerhans c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hand
A hand is a prehensile, multi-fingered appendage located at the end of the forearm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs. A few other vertebrates such as the koala (which has two opposable thumbs on each "hand" and fingerprints extremely similar to human fingerprints) are often described as having "hands" instead of paws on their front limbs. The raccoon is usually described as having "hands" though opposable thumbs are lacking. Some evolutionary anatomists use the term ''hand'' to refer to the appendage of digits on the forelimb more generally—for example, in the context of whether the three digits of the bird hand involved the same homologous loss of two digits as in the dinosaur hand. The human hand usually has five digits: four fingers plus one thumb; these are often referred to collectively as five fingers, however, whereby the thumb is included as one of the fingers. It has 27 bones, not including the sesamoid bone, the number o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sole (foot)
The sole is the bottom of the foot. In humans the sole of the foot is anatomically referred to as the plantar aspect. Structure The glabrous skin on the sole of the foot lacks the hair and pigmentation found elsewhere on the body, and it has a high concentration of sweat pores. The sole contains the thickest layers of skin on the body due to the weight that is continually placed on it. It is crossed by a set of creases that form during the early stages of embryonic development. Like those of the palm, the sweat pores of the sole lack sebaceous glands. The sole is a sensory organ by which we can perceive the ground while standing and walking. The subcutaneous tissue in the sole has adapted to deal with the high local compressive forces on the heel and the ball (between the toes and the arch) by developing a system of "pressure chambers." Each chamber is composed of internal fibrofatty tissue covered by external collagen connective tissue. The septa (internal walls) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epidermolytic Palmoplantar Keratoderma
Epidermolytic ichthyosis (EI), also known as bullous epidermis ichthyosis (BEI), epidermolytic hyperkeratosis (EHK), bullous congenital ichthyosiform erythroderma (BCIE), bullous ichthyosiform erythrodermaFreedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. . or bullous congenital ichthyosiform erythroderma Brocq, is a rare and severe form of ichthyosis that affects around 1 in 300,000 people. It is caused by a genetic mutation, and thus cannot be completely cured without some form of gene therapy. While some research has been done into possible gene therapy treatments, the work hasn't yet been successfully developed to the stage where it can be routinely given to patients. The condition involves the clumping of keratin filaments.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . Presentation Epidermolytic hyperkeratosis is a skin disorder that is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
