Related Research Articles
Glycosaminoglycans (GAGs) or mucopolysaccharides are long, linear polysaccharides consisting of repeating disaccharide units. The repeating two-sugar unit consists of a uronic sugar and an amino sugar, except in the case of the sulfated glycosaminoglycan keratan, where, in place of the uronic sugar there is a galactose unit. GAGs are found in vertebrates, invertebrates and bacteria. Because GAGs are highly polar molecules and attract water; the body uses them as lubricants or shock absorbers.
Fibroblast growth factors (FGF) are a family of cell signalling proteins produced by macrophages; they are involved in a wide variety of processes, most notably as crucial elements for normal development in animal cells. Any irregularities in their function lead to a range of developmental defects. These growth factors typically act as systemic or locally circulating molecules of extracellular origin that activate cell surface receptors. A defining property of FGFs is that they bind to heparin and to heparan sulfate. Thus, some are sequestered in the extracellular matrix of tissues that contains heparan sulfate proteoglycans and are released locally upon injury or tissue remodeling.
Perlecan (PLC) also known as basement membrane-specific heparan sulfate proteoglycan core protein (HSPG) or heparan sulfate proteoglycan 2 (HSPG2), is a protein that in humans is encoded by the HSPG2 gene. The HSPG2 gene codes for a 4,391 amino acid protein with a molecular weight of 468,829. It is one of the largest known proteins. The name perlecan comes from its appearance as a "string of pearls" in rotary shadowed images.
Heparan sulfate (HS) is a linear polysaccharide found in all animal tissues. It occurs as a proteoglycan in which two or three HS chains are attached in close proximity to cell surface or extracellular matrix proteins. In this form, HS binds to a variety of protein ligands, including Wnt, and regulates a wide range of biological activities, including developmental processes, angiogenesis, blood coagulation, abolishing detachment activity by GrB, and tumour metastasis. HS has also been shown to serve as cellular receptor for a number of viruses, including the respiratory syncytial virus. One study suggests that cellular heparan sulfate has a role in SARS-CoV-2 Infection, particularly when the virus attaches with ACE2.
In biochemistry, sulfatases EC 3.1.6.- are a class of enzymes of the esterase class that catalyze the hydrolysis of sulfate esters into an alcohol and a bisulfate:
In enzymology, a [heparan sulfate]-glucosamine 3-sulfotransferase 1 is an enzyme that catalyzes the chemical reaction
In enzymology, a [heparan sulfate]-glucosamine 3-sulfotransferase 2 is an enzyme that catalyzes the chemical reaction
In enzymology, a [heparan sulfate]-glucosamine 3-sulfotransferase 3 is an enzyme that catalyzes the chemical reaction
Heparanase, also known as HPSE, is an enzyme that acts both at the cell-surface and within the extracellular matrix to degrade polymeric heparan sulfate molecules into shorter chain length oligosaccharides.
Carbohydrate sulfotransferase 1 is an enzyme that in humans is encoded by the CHST1 gene.
Sulfatase 1, also known as SULF1, is an enzyme which in humans is encoded by the SULF1 gene.
Heparan sulfate glucosamine 3-O-sulfotransferase 3A1 is an enzyme that in humans is encoded by the HS3ST3A1 gene.
Heparan sulfate glucosamine 3-O-sulfotransferase 1 is an enzyme that in humans is encoded by the HS3ST1 gene.
Bifunctional heparan sulfate N-deacetylase/N-sulfotransferase 2 is an enzyme that in humans is encoded by the NDST2 gene.
Heparan sulfate 2-O-sulfotransferase 1 is an enzyme that in humans is encoded by the HS2ST1 gene.
Heparan sulfate glucosamine 3-O-sulfotransferase 3B1 is an enzyme that in humans is encoded by the HS3ST3B1 gene. Heparan sulfate biosynthetic enzymes are key components in generating myriad distinct heparan sulfate fine structures that carry out multiple biologic activities. The enzyme encoded by this gene is a member of the heparan sulfate biosynthetic enzyme family. It is a type II integral membrane protein and possesses heparan sulfate glucosaminyl 3-O-sulfotransferase activity ( HS3ST3A1). The Sulfotransferase domain of this enzyme is highly similar to the same domain of heparan sulfate D-glucosaminyl 3-O-sulfotransferase 3A1 and these two enzymes sulfate an identical disaccharide. This gene is widely expressed, with the most abundant expression in liver and placenta.
Heparan sulfate glucosamine 3-O-sulfotransferase 2 is an enzyme that in humans is encoded by the HS3ST2 gene.
In biochemistry, carbohydrate sulfotransferases are enzymes within the class of sulfotransferases which catalyze the transfer of the sulfate functional group to carbohydrate groups in glycoproteins and glycolipids. Carbohydrates are used by cells for a wide range of functions from structural purposes to extracellular communication. Carbohydrates are suitable for such a wide variety of functions due to the diversity in structure generated from monosaccharide composition, glycosidic linkage positions, chain branching, and covalent modification. Possible covalent modifications include acetylation, methylation, phosphorylation, and sulfation. Sulfation, performed by carbohydrate sulfotransferases, generates carbohydrate sulfate esters. These sulfate esters are only located extracellularly, whether through excretion into the extracellular matrix (ECM) or by presentation on the cell surface. As extracellular compounds, sulfated carbohydrates are mediators of intercellular communication, cellular adhesion, and ECM maintenance.
Heparan sulfate 6-sulfotransferases catalyses the transfer of sulfate from adenosine 3'-phosphate, 5'-phosphosulfate to the 6th position of the N-sulfoglucosamine residue in heparan sulfate.
Heparan sulfate 6-O-sulfotransferase 2 is a protein that in humans is encoded by the HS6ST2 gene.
References
- ↑ Li J, Shworak NW, Simons M (2002). "Increased responsiveness of hypoxic endothelial cells to FGF2 is mediated by HIF-1alpha-dependent regulation of enzymes involved in synthesis of heparan sulfate FGF2-binding sites". J. Cell Sci. 115 (Pt 9): 1951–1959. doi:10.1242/jcs.115.9.1951. PMID 11956326. (This paper currently has an expression of concern, see doi:10.1242/jcs.260635, PMID 36239191 )