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Sphingosine Kinase
Sphingosine kinase (SphK) is a conserved lipid kinase that catalyzes formation sphingosine-1-phosphate (S1P) from the precursor sphingolipid sphingosine. Sphingolipid metabolites, such as ceramide, sphingosine and sphingosine-1-phosphate, are lipid second messengers involved in diverse cellular processes. There are two forms of SphK, SphK1 and SphK2. SphK1 is found in the cytosol of eukaryotic cells, and migrates to the plasma membrane upon activation. SphK2 is localized to the nucleus. Function S1P has been shown to regulate diverse cellular processes. It has been characterized as a lipid signaling molecule with dual function. On one hand, it exerts its actions extracellularly by binding to the five different S1P receptors that couple to a variety of G-proteins to regulate diverse biological functions, ranging from cell growth and survival to effector functions, such as proinflammatory mediator synthesis. On the other hand, it appears to act as an intracellular sec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphingosine Kinase 1
Sphingosine kinase 1 is an enzyme that in humans is encoded by the ''SPHK1'' gene. Sphingosine kinase 1 phosphorylates sphingosine to sphingosine-1-phosphate (S1P). SK1 is normally a cytosolic protein but is recruited to membranes rich in phosphatidate (PA), a product of phospholipase D (PLD). Sphingosine-1-phosphate (S1P) is a novel lipid messenger with both intracellular and extracellular functions. Intracellularly, it regulates proliferation and survival, and extracellularly, it is a ligand for EDG1. Various stimuli increase cellular levels of S1P by activation of sphingosine kinase (SPHK), the enzyme that catalyzes the phosphorylation of sphingosine. Competitive inhibitors of SPHK block formation of S1P and selectively inhibit cellular proliferation induced by a variety of factors, including platelet-derived growth factor and serum. Interactions SPHK1 has been shown to interact with TRAF2 TNF receptor-associated factor 2 is a protein that in humans is encode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorylation
In biochemistry, phosphorylation is described as the "transfer of a phosphate group" from a donor to an acceptor. A common phosphorylating agent (phosphate donor) is ATP and a common family of acceptor are alcohols: : This equation can be written in several ways that are nearly equivalent that describe the behaviors of various protonated states of ATP, ADP, and the phosphorylated product. As is clear from the equation, a phosphate group per se is not transferred, but a phosphoryl group (PO3-). Phosphoryl is an electrophile. This process and its inverse, dephosphorylation, are common in biology. Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License. Protein phosphorylation often activates (or deactivates) many enzymes. During respiration Phosphorylation is essential to the processes of both anaerobic and aerobic respiration, which involve the production of adenosine triphosphate (ATP), the "high-energy" exc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Josiah Bartlet
Josiah Edward "Jed" Bartlet is a fictional character from the American television serial drama ''The West Wing'' created by Aaron Sorkin and portrayed by actor Martin Sheen. The role earned Sheen a Golden Globe Award for Best Actor – Television Series Drama in 2001, as well as two SAG Awards. Bartlet's tenure as a fictional Democratic President of the United States is a preeminent aspect of the series. His origin as a recurring character evolved due to Sheen's acting finesse; Sorkin and fellow ''West Wing'' writers shaped Bartlet's role within the show accordingly. The first season depicts part of Bartlet's first two years in the White House. The remainder of the series fleshes out the details of Bartlet's administration, including friction between his policies and those of the Republican-dominated Congress, his tribulations with multiple sclerosis, his reelection, and the campaign of his successor, Matt Santos. Bartlet is characterized by manifest integrity, quick witti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The West Wing
''The West Wing'' is an American political drama television series created by Aaron Sorkin that was originally broadcast on NBC from September 22, 1999, to May 14, 2006. The series is set primarily in the West Wing of the White House, where the Oval Office and offices of presidential senior personnel are located, during the fictional two-term Democratic Party (United States), Democratic administration of President Josiah Bartlet. ''The West Wing'' was produced by Warner Bros. Television and features an List of The West Wing characters, ensemble cast, including Rob Lowe, Dulé Hill, Allison Janney, Richard Schiff, John Spencer (actor), John Spencer, Bradley Whitford, Martin Sheen, Janel Moloney, and Stockard Channing. For the first four seasons, there were three executive producers: Sorkin (lead writer of the first four seasons), Thomas Schlamme (primary director), and John Wells (filmmaker), John Wells. After Sorkin left the series at the end of the fourth season, Wells assume ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The West Wing (season 3)
The third season of the American political drama television series ''The West Wing'' aired in the United States on NBC from October 3, 2001 to May 22, 2002 and consisted of 21 episodes and 2 special episodes. Production The season premiere was delayed by the September 11, 2001 terrorist attacks in the United States. When the season did return, the first episode was a special episode titled "Isaac and Ishmael," in which the main cast paid tribute to those affected by the attacks and informed viewers about what to expect from the delayed premiere. Series creator Aaron Sorkin acknowledged in October 2002 that the terrorism-related plots designed to keep the series relevant after the real-life attacks were awkward at times, saying "from week to week, you felt like you were writing the show handcuffed, a little bit. I didn't know how to write it anymore. It was a constant search for what I wasn't doing that used to make the show work. Maybe there was a way to make it work. There pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphk1 Diag B
Sphingosine kinase 1 is an enzyme that in humans is encoded by the ''SPHK1'' gene. Sphingosine kinase 1 phosphorylates sphingosine to sphingosine-1-phosphate (S1P). SK1 is normally a cytosolic protein but is recruited to membranes rich in phosphatidate (PA), a product of phospholipase D (PLD). Sphingosine-1-phosphate (S1P) is a novel lipid messenger with both intracellular and extracellular functions. Intracellularly, it regulates proliferation and survival, and extracellularly, it is a ligand for EDG1. Various stimuli increase cellular levels of S1P by activation of sphingosine kinase (SPHK), the enzyme that catalyzes the phosphorylation of sphingosine. Competitive inhibitors of SPHK block formation of S1P and selectively inhibit cellular proliferation induced by a variety of factors, including platelet-derived growth factor and serum. Interactions SPHK1 has been shown to interact with TRAF2 TNF receptor-associated factor 2 is a protein that in humans is encoded by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbohydrate
A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' may differ). This formula does not imply direct covalent bonding between hydrogen and oxygen atoms; for example, in , hydrogen is covalently bonded to carbon, not oxygen. While the 2:1 hydrogen-to-oxygen ratio is characteristic of many carbohydrates, exceptions exist. For instance, uronic acids and deoxy-sugars like fucose deviate from this precise stoichiometric definition. Conversely, some compounds conforming to this definition, such as formaldehyde and acetic acid, are not classified as carbohydrates. The term is predominantly used in biochemistry, functioning as a synonym for saccharide (), a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups: monosaccharides, disaccharides, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphocholine
Phosphocholine is an intermediate in the synthesis of phosphatidylcholine in tissues. Phosphocholine is made in a reaction, catalyzed by choline kinase, that converts ATP and choline into phosphocholine and ADP. Phosphocholine is a molecule found, for example, in lecithin. In nematodes and human placentas, phosphocholine is selectively attached to other proteins as a posttranslational modification to suppress an immune response by their hosts. It is also one of the binding targets of C-reactive protein (CRP). Thus, when a cell is damaged, CRP binds to phosphocholine, beginning the recognition and phagocytotic immunologic response. Phosphocholine is a natural constituent of hens' eggs (and many other eggs) often used in biomimetic membrane studies. See also * Alkylphosphocholines * Choline * Phosphoethanolamine Phosphorylethanolamine or phosphoethanolamine is an ethanolamine derivative that is used to construct two different categories of phospholipids. One categor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amide
In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a chemical compound, compound with the general formula , where R, R', and R″ represent any group, typically organyl functional group, groups or hydrogen atoms. The amide group is called a peptide bond when it is part of the Polymer backbone, main chain of a protein, and an isopeptide bond when it occurs in a side chain, as in asparagine and glutamine. It can be viewed as a Derivative (chemistry), derivative of a carboxylic acid () with the hydroxyl group () replaced by an amino group (); or, equivalently, an acyl group, acyl (alkanoyl) group () joined to an amino group. Common amides are formamide (), acetamide (), benzamide (), and dimethylformamide (). Some uncommon examples of amides are ''N''-chloroacetamide () and chloroformamide (). Amides are qualified as primary (chemistry), primary, secondary (chemistry), secondary, and tertiary (chemistry), tertiary according to the number of acyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatty Acid
In chemistry, in particular in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated and unsaturated compounds#Organic chemistry, saturated or unsaturated. Most naturally occurring fatty acids have an Branched chain fatty acids, unbranched chain of an even number of carbon atoms, from 4 to 28. Fatty acids are a major component of the lipids (up to 70% by weight) in some species such as microalgae but in some other organisms are not found in their standalone form, but instead exist as three main classes of esters: triglycerides, phospholipids, and cholesteryl esters. In any of these forms, fatty acids are both important diet (nutrition), dietary sources of fuel for animals and important structural components for cell (biology), cells. History The concept of fatty acid (''acide gras'') was introduced in 1813 by Michel Eugène Chevreul, though he initially used some variant terms: ''graisse acide'' and ''acide huileux'' ("acid fat" and "oi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphinganine
Safingol is a lyso-sphingolipid protein kinase inhibitor. It has the molecular formula C18H39NO2 and is a colorless solid. Medicinally, safingol has demonstrated promising anticancer potential as a modulator of multi-drug resistance and as an inducer of necrosis. The administration of safingol alone has not been shown to exert a significant effect on tumor cell growth. However, preclinical and clinical studies have shown that combining safingol with conventional chemotherapy agents such as fenretinide, vinblastine, irinotecan and mitomycin C can dramatically potentiate their antitumor effects. In phase I clinical trials, it was found to be safe to co-administer with cisplatin, but caused reversible dose-dependent hepatotoxicity. Mechanism The underlying mechanism by which safingol induces cell death is poorly understood. It is believed to exert a variety of inhibitory effects, resulting in a series of cascades that result in accidental necrotic cell death brought about by r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serine
Serine (symbol Ser or S) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α- amino group (which is in the protonated − form under biological conditions), a carboxyl group (which is in the deprotonated − form under biological conditions), and a side chain consisting of a hydroxymethyl group, classifying it as a polar amino acid. It can be synthesized in the human body under normal physiological circumstances, making it a nonessential amino acid. It is encoded by the codons UCU, UCC, UCA, UCG, AGU and AGC. Occurrence This compound is one of the proteinogenic amino acids. Only the L- stereoisomer appears naturally in proteins. It is not essential to the human diet, since it is synthesized in the body from other metabolites, including glycine. Serine was first obtained from silk protein, a particularly rich source, in 1865 by Emil Cramer. Its name is derived from the Latin for silk, '' sericum''. Serine's structure was established in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
