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LEKTI
Lympho-epithelial Kazal-type-related inhibitor (LEKTI) also known as serine protease inhibitor Kazal-type 5 (SPINK5) is a protein that in humans is encoded by the ''SPINK5'' gene. Structure and function LEKTI is a large multidomain serine protease inhibitor expressed in stratified epithelial tissue. It consists of 15 domains that are cleaved into smaller, functional fragments by the protease furin. Only two of these domains (2 and 15) contain 6 evenly spaced cysteines responsible for 3 intramolecular disulfide bonds characteristic of Kazal-type related inhibitors. The remaining domains contain 4 cysteines. These disulfide bonds force the molecule into a rigid conformation that enables the protein to interact with a target protease via an extended beta-sheet. All domains (excepting 1, 2 and 15) contain an arginine at P1, indicating trypsin-like proteases are the likely targets. In the epidermis, LEKTI is implicated in the regulation of desquamation via its ability to selectivel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Netherton Syndrome
Netherton syndrome is a severe, autosomal recessive form of ichthyosis associated with mutations in the ''SPINK5'' gene. It is named after Earl W. Netherton (1910–1985), an American dermatologist who discovered it in 1958.Netherton, E. W. A unique case of trichorrhexis nodosa: 'bamboo hairs.'. Arch. Derm. 78: 483-487, 1958. Signs and symptoms Netherton syndrome is characterized by chronic skin inflammation, universal pruritus (itch), severe dehydration, and stunted growth. Patients with this disorder tend to have a hair shaft defect (trichorrhexis invaginata), also known as "bamboo hair". The disrupted skin barrier function in affected individuals also presents a high susceptibility to infection and allergy, leading to the development of scaly, reddish skin similar to atopic dermatitis. In severe cases, these atopic manifestations persist throughout the individual's life, and consequently post-natal mortality rates are high. In less severe cases, this develops into the milder ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LEKTI-2
Lympho-epithelial Kazal-type related inhibitor 2 (LEKTI-2) is a protein encoded by the ''SPINK9'' gene in humans. ''SPINK9'' is a member of a gene family cluster located on chromosome 5q33.1, which includes ''SPINK5'' and ''SPINK6''. LEKTI-2 is an inhibitor of KLK5. Desquamation The outer layer of the epidermis is called the stratum corneum. In the stratum corneum terminally differentiated corneocytes are held together by corneodesmosomes. In order for desquamation to occur, corneodesmosomes need to be fully degraded. KLK5 and KLK7 are two serine proteases that degrade corneodesmosomes. LEKTI-2 regulates corneodesmosome degradation by inhibiting KLK5. In acral (palm and sole) skin, where desquamation needs to be delayed, ''SPINK9'' expression is strongly upregulated. The resulting high level of LEKTI-2 delays corneodesmosome degradation, thereby allowing the epidermis to form a thick protective stratum corneum layer. Clinical Significance SPINK9 is overexpressed in lichen simplex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KLK7
Kallikrein-related peptidase 7 (KLK7) is a serine protease that in humans is encoded by the ''KLK7'' gene. KLK7 was initially purified from the epidermis and characterised as stratum corneum chymotryptic enzyme (SCCE). It was later identified as the seventh member of the human kallikrein family, which includes fifteen homologous serine proteases located on chromosome 19 (19q13). Gene Alternative splicing of the ''KLK7'' gene results in two transcript variants encoding the same protein. Function KLK7 is secreted as an inactive zymogen in the stratum granulosum layer of the epidermis, requiring proteolytic cleavage of the short N-terminal pro-region to liberate activated enzyme. This may be performed by KLK5 or matriptase, which are ''in vitro'' activators of KLK7. Once active, KLK7 is able to cleave desmocollin and corneodesmosin. These proteins constitute the extracellular component of corneodesmosomes, intercellular cohesive structures which link the intermediate filaments ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KLK14
Kallikrein-14 is a protein that in humans is encoded by the ''KLK14'' gene. Kallikreins are a subgroup of serine proteases having diverse physiological functions. Growing evidence suggests that many kallikreins are implicated in carcinogenesis and some have potential as novel cancer, skin disorders and other disease biomarkers. This gene is one of the fifteen kallikrein subfamily members located in a cluster on chromosome 19. Apart from its common transcript, an additional transcript variant has been described but its difference in function and full length nature has not been determined. KLK14 displays optimal trypsin-like activity at an alkaline pH of 8.0 and remains active in the pH ranges of 5.0 - 9.0 and is produced as a zymogen, but can function also in a chymotrypsin-like fashion. Activation of KLK14 is mediated by KLK5 and after KLK14 activation, it further amplifies the activity of KLK proteases by a positive feedback loop via cleavage of pro-KLK5, which is a central play ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome 5 (human)
Chromosome 5 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 5 spans about 181 million base pairs (the building blocks of DNA) and represents almost 6% of the total DNA in cells. Chromosome 5 is the 5th largest human chromosome, yet has one of the lowest gene densities. This is partially explained by numerous gene-poor regions that display a remarkable degree of non-coding and syntenic conservation with non-mammalian vertebrates, suggesting they are functionally constrained. Because chromosome 5 is responsible for many forms of growth and development (cell divisions) changes may cause cancers. One example would be acute myeloid leukemia (AML). Genes Number of genes The following are some of the gene count estimates of human chromosome 5. Because researchers use different approaches to genome annotation their predictions of the number of genes on each chromosome varies (for technical details, see gene prediction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SPINK6
Serine protease inhibitor Kazal-type 6 (SPINK6) is a protein encoded by the ''SPINK6'' gene in humans. It is a potent inhibitor of epidermal proteases involved in maintaining skin homeostasis, including KLK5, KLK7 and KLK14. ''SPINK6'' is a member of a gene family cluster located on chromosome 5q33.1, which includes ''SPINK5'' and ''SPINK9 Lympho-epithelial Kazal-type related inhibitor 2 (LEKTI-2) is a protein encoded by the ''SPINK9'' gene in humans. ''SPINK9'' is a member of a gene family cluster located on chromosome 5q33.1, which includes '' SPINK5'' and '' SPINK6''. LEKTI-2 is ...''. See also * Kazal-type serine protease inhibitor domain References Proteins {{gene-5-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KLK5
Kallikrein-5, formerly known as stratum corneum tryptic enzyme (SCTE), is a serine protease expressed in the epidermis. In humans it is encoded by the ''KLK5'' gene. This gene is one of the fifteen kallikrein subfamily members located in a cluster on chromosome 19. Its expression is up-regulated by estrogens and progestins. Alternative splicing results in multiple transcript variants encoding the same protein. KLK5 has been suggested to regulate cell shedding (desquamation) in conjunction with KLK7 and KLK14, given its ability to degrade proteins which form the extracellular component of cell junctions in the stratum corneum. It is proposed that KLK5 regulates this process since it is able to self-activate in addition to activating KLK7 and KLK14. References Further reading * * * * * * * * * * * * * * * * * External links * The MEROPS MEROPS is an online database for peptidases (also known as proteases, proteinases and proteolytic enzymes) and their inhibitors. The c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elastase
In molecular biology, elastase is an enzyme from the class of ''proteases (peptidases)'' that break down proteins. In particular, it is a serine protease. Forms and classification Eight human genes exist for elastase: Some bacteria (including ''Pseudomonas aeruginosa'') also produce elastase. In bacteria, elastase is considered a virulence factor. Function Elastase breaks down elastin, an elastic fibre that, together with collagen, determines the mechanical properties of connective tissue. The neutrophil form breaks down the ''Outer membrane protein A'' (OmpA) of '' E. coli'' and other Gram-negative bacteria. Elastase also has the important immunological role of breaking down Shigella virulence factors. This is accomplished through the cleavage of peptide bonds in the target proteins. The specific peptide bonds cleaved are those on the carboxyl side of small, hydrophobic amino acids such as glycine, alanine, and valine. For more on how this is accomplished, see serine p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cathepsin G
Cathepsin G is a protein that in humans is encoded by the ''CTSG'' gene. It is one of the three serine proteases of the chymotrypsin family that are stored in the azurophil granules, and also a member of the peptidase S1 protein family. Cathepsin G plays an important role in eliminating intracellular pathogens and breaking down tissues at inflammatory sites, as well as in anti-inflammatory response. Structure Gene The CTSG gene is located at chromosome 14q11.2, consisting of 5 exons. Each residue of the catalytic triad is located on a separate exon. Five polymorphisms have been identified by scanning the entire coding region. Cathepsin G is one of those homologous protease that evolved from a common ancestor by gene duplication. Protein Cathepsin G is a 255-amino-acid-residue protein including an 18-residue signal peptide, a two-residue activation peptide at the N-terminus and a carboxy terminal extension. The activity of cathepsin G depends on a catalytic triad composed of as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtilisin
Subtilisin is a protease (a protein-digesting enzyme) initially obtained from ''Bacillus subtilis''. Subtilisins belong to subtilases, a group of serine proteases that – like all serine proteases – initiate the nucleophilic attack on the peptide (amide) bond through a serine residue at the active site. Subtilisins typically have molecular weights 27kDa. They can be obtained from certain types of soil bacteria, for example, ''Bacillus amyloliquefaciens'' from which they are secreted in large amounts. Nomenclature Subtilisin is also commercially known as ''Alcalase®'', ''Endocut-02L'', ''ALK-enzyme'', ''bacillopeptidase'', ''Bacillus subtilis alkaline proteinase bioprase'', ''bioprase AL'', ''colistinase'', ''genenase I'', ''Esperase®'', ''maxatase'', ''protease XXVII'', ''thermoase'', ''superase'', ''subtilisin DY'', ''subtilopeptidase'', ''SP 266'', ''Savinase®'', ''kazusase'', ''protease VIII'', ''protin A 3L'', ''Savinase®'', ''orientase 10B'', ''protease S.'' It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmin
Plasmin is an important enzyme () present in blood that degrades many blood plasma proteins, including fibrin clots. The degradation of fibrin is termed fibrinolysis. In humans, the plasmin protein (in the zymogen form of plasminogen) is encoded by the ''PLG'' gene. Function Plasmin is a serine protease that acts to dissolve fibrin blood clots. Apart from fibrinolysis, plasmin proteolyses proteins in various other systems: It activates collagenases, some mediators of the complement system, and weakens the wall of the Graafian follicle, leading to ovulation. Plasmin is also integrally involved in inflammation. It cleaves fibrin, fibronectin, thrombospondin, laminin, and von Willebrand factor. Plasmin, like trypsin, belongs to the family of serine proteases. Plasmin is released as a zymogen called plasminogen (PLG) from the liver into the systemic circulation. Two major glycoforms of plasminogen are present in humans - type I plasminogen contains two glycosylation moieties ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trypsin
Trypsin is an enzyme in the first section of the small intestine that starts the digestion of protein molecules by cutting these long chains of amino acids into smaller pieces. It is a serine protease from the PA clan superfamily, found in the digestive system of many vertebrates, where it hydrolyzes proteins. Trypsin is formed in the small intestine when its proenzyme form, the trypsinogen produced by the pancreas, is activated. Trypsin cuts peptide chains mainly at the carboxyl side of the amino acids lysine or arginine. It is used for numerous biotechnological processes. The process is commonly referred to as trypsin proteolysis or trypsinization, and proteins that have been digested/treated with trypsin are said to have been trypsinized. Trypsin was discovered in 1876 by Wilhelm Kühne and was named from the Ancient Greek word for rubbing since it was first isolated by rubbing the pancreas with glycerin. Function In the duodenum, trypsin catalyzes the hydrolysis of pept ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
