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Pigment Epithelium-derived Factor
Pigment epithelium-derived factor (PEDF) also known as serpin F1 (SERPINF1), is a multifunctional secreted protein that has anti-angiogenic, anti-tumorigenic, and neurotrophic functions. Found in vertebrates, this 50 kDa protein is being researched as a therapeutic candidate for treatment of such conditions as choroidal neovascularization, heart disease, and cancer. In humans, pigment epithelium-derived factor is encoded by the ''SERPINF1'' gene. Discovery Pigment epithelium-derived factor (PEDF) was originally discovered by Joyce Tombran-Tink and Lincoln Johnson in the late 1980s. This group was studying human retinal cell development by identifying secreted factors produced by the retinal pigmented epithelium (RPE), a layer of cells that supports the retina. Upon noticing RPE produced a factor that promoted the differentiation of primitive retinal cells into cells of a neuronal phenotype, they set out to determine the identity of the factor. They isolated proteins unique to ... [...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] |
Promoter (biology)
In genetics, a promoter is a sequence of DNA to which proteins bind to initiate transcription of a single RNA transcript from the DNA downstream of the promoter. The RNA transcript may encode a protein (mRNA), or can have a function in and of itself, such as tRNA or rRNA. Promoters are located near the transcription start sites of genes, upstream on the DNA (towards the 5' region of the sense strand). Promoters can be about 100–1000 base pairs long, the sequence of which is highly dependent on the gene and product of transcription, type or class of RNA polymerase recruited to the site, and species of organism. Promoters control gene expression in bacteria and eukaryotes. RNA polymerase must attach to DNA near a gene for transcription to occur. Promoter DNA sequences provide an enzyme binding site. The -10 sequence is TATAAT. -35 sequences are conserved on average, but not in most promoters. Artificial promoters with conserved -10 and -35 elements transcribe more slowly. All D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kringle Domain
Kringle Domains are autonomous protein domains that fold into large loops stabilized by 3 disulfide linkages. These are important in protein–protein interactions with blood coagulation factors. Their name refers to the Kringle, a Scandinavian pastry which they somewhat resemble. Kringle domains have been found in plasminogen, hepatocyte growth factors, prothrombin, and apolipoprotein(a). Kringles are found throughout the blood clotting and fibrinolytic proteins. Kringle domains are believed to play a role in binding mediators (e.g., membranes, other proteins or phospholipids), and in the regulation of proteolytic activity. Kringle domains are characterised by a triple loop, 3-disulfide bridge structure, whose conformation is defined by a number of hydrogen bonds and small pieces of anti-parallel beta-sheet. They are found in a varying number of copies in some plasma proteins including prothrombin and urokinase-type plasminogen activator, which are serine proteases belonging ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasminogen
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 moie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Crystallography
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles and intensities of these diffracted beams, a crystallographer can produce a three-dimensional picture of the density of electrons within the crystal. From this electron density, the mean positions of the atoms in the crystal can be determined, as well as their chemical bonds, their crystallographic disorder, and various other information. Since many materials can form crystals—such as salts, metals, minerals, semiconductors, as well as various inorganic, organic, and biological molecules—X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences among various mat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosylation
Glycosylation is the reaction in which a carbohydrate (or ' glycan'), i.e. a glycosyl donor, is attached to a hydroxyl or other functional group of another molecule (a glycosyl acceptor) in order to form a glycoconjugate. In biology (but not always in chemistry), glycosylation usually refers to an enzyme-catalysed reaction, whereas glycation (also 'non-enzymatic glycation' and 'non-enzymatic glycosylation') may refer to a non-enzymatic reaction (though in practice, 'glycation' often refers more specifically to Maillard-type reactions). Glycosylation is a form of co-translational and post-translational modification. Glycans serve a variety of structural and functional roles in membrane and secreted proteins. The majority of proteins synthesized in the rough endoplasmic reticulum undergo glycosylation. Glycosylation is also present in the cytoplasm and nucleus as the ''O''-GlcNAc modification. Aglycosylation is a feature of engineered antibodies to bypass glycosylation. Five clas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Localization Sequence
A nuclear localization signal ''or'' sequence (NLS) is an amino acid sequence that 'tags' a protein for import into the cell nucleus by nuclear transport. Typically, this signal consists of one or more short sequences of positively charged lysines or arginines exposed on the protein surface. Different nuclear localized proteins may share the same NLS. An NLS has the opposite function of a nuclear export signal (NES), which targets proteins out of the nucleus. Types Classical These types of NLSs can be further classified as either monopartite or bipartite. The major structural differences between the two are that the two basic amino acid clusters in bipartite NLSs are separated by a relatively short spacer sequence (hence bipartite - 2 parts), while monopartite NLSs are not. The first NLS to be discovered was the sequence PKKKRKV in the SV40 Large T-antigen (a monopartite NLS). The NLS of nucleoplasmin, KR AATKKAGQAKKK, is the prototype of the ubiquitous bipartite signal: two cluster ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BLAST
Blast or The Blast may refer to: * Explosion, a rapid increase in volume and release of energy in an extreme manner *Detonation, an exothermic front accelerating through a medium that eventually drives a shock front Film * ''Blast'' (1997 film), starring Andrew Divoff * ''Blast'' (2000 film), starring Liesel Matthews * ''Blast'' (2004 film), an action comedy film * ''Blast!'' (1972 film) or ''The Final Comedown'', an American drama * ''BLAST!'' (2008 film), a documentary about the BLAST telescope * '' A Blast'', a 2014 film directed by Syllas Tzoumerkas Magazines * ''Blast'' (magazine), a 1914–15 literary magazine of the Vorticist movement * ''Blast'' (U.S. magazine), a 1933–34 American short-story magazine * ''The Blast'' (magazine), a 1916–17 American anarchist periodical Music * Blast (American band), a hardcore punk band * Blast (Russian band), an indie band * ''Blast'' (album), by Holly Johnson, 1989 * ''The Blast'' (album), by Yuvan Shankar Raja, 1999 * " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angiogenesis Inhibitor
An angiogenesis inhibitor is a substance that inhibits the growth of new blood vessels (angiogenesis). Some angiogenesis inhibitors are endogenous and a normal part of the body's control and others are obtained exogenously through drugs, pharmaceutical drugs or diet (nutrition), diet. While angiogenesis is a critical part of wound healing and other favorable processes, certain types of angiogenesis are associated with the growth of malignant tumors. Thus angiogenesis inhibitors have been closely studied for possible cancer treatment. Angiogenesis inhibitors were once thought to have potential as a "silver bullet" treatment applicable to many types of cancer, but the limitations of anti-angiogenic therapy have been shown in practice. Nonetheless, inhibitors are used to effectively treat cancer, macular degeneration in the eye, and other diseases that involve a proliferation of blood vessels. Mechanism of action When a tumor stimulates the growth of new vessels, it is said to have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha amino acids appear in the genetic code. Amino acids can be classified according to the locations of the core structural functional groups, as Alpha and beta carbon, alpha- , beta- , gamma- or delta- amino acids; other categories relate to Chemical polarity, polarity, ionization, and side chain group type (aliphatic, Open-chain compound, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid '' residues'' form the second-largest component (water being the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. It is thought that they played a key role in enabling life ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SERPINF2
Alpha 2-antiplasmin (or α2-antiplasmin or plasmin inhibitor) is a serine protease inhibitor (serpin) responsible for inactivating plasmin. Plasmin is an important enzyme that participates in fibrinolysis and degradation of various other proteins. This protein is encoded by the SERPINF2 gene. Role in disease Very few cases (<20) of A2AP deficiency have been described. As plasmin degrades blood clots, impaired inhibition of plasmin leads to a bleeding tendency, which was severe in the cases reported. In liver , there is decreased production of alpha 2-antiplasmin, leading to decreased inactivation of and an increase in |
USF1
Upstream stimulatory factor 1 is a protein that in humans is encoded by the ''USF1'' gene. Function This gene encodes a member of the basic helix-loop-helix leucine zipper family and can function as a cellular transcription factor. The encoded protein can activate transcription through pyrimidine-rich initiator (Inr) elements and E-box motifs. This gene has been linked to familial combined hyperlipidemia (FCHL). Two transcript variants encoding distinct isoforms have been identified for this gene. A study of mice suggested reduced USF1 levels increases metabolism in brown fat. Interactions USF1 (human gene) has been shown to interact with USF2, FOSL1 and GTF2I General transcription factor II-I is a protein that in humans is encoded by the ''GTF2I'' gene. Function This gene encodes a multifunctional phosphoprotein, TFII-I, with roles in transcription and signal transduction. Haploinsuffiency (deletio .... References Further reading * * * * * * * * * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
