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Ceramide Synthase 4
Ceramide synthase 4 (CerS4) is an enzyme that in humans is encoded by the CERS4 gene and is one of the least studied of the ceramide synthases. Function and distribution CerS4 synthesizes ceramides containing C18-22 fatty acids in a fumonisin B1-independent manner. It is expressed at highest levels in skin, leukocytes, heart and liver, although at much lower levels than other ceramide synthases. Tissue and cellular distribution CerS4 (TRH1) mRNA was found in all tissues and is strongly expressed in skin and muscle Clinical significance In a 2009 study of breast cancer, total ceramide synthase levels were increased in malignant tissue, and CerS4 was one of three ceramide synthases to show an increase in mRNA levels. A significant correlation was found between CerS4 and CerS2/CERS6 (gene), CerS6 expression. Unlike CerS1 and CerS5, CerS4 does not sensitize cells to chemotherapeutic drugs. CerS4 may also be involved in the control of body weight and food intake. Upon administrati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
