Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.4.99.7 (sialyltransferase)
 1,534 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Avian influenza viruses preferentially use alpha2,3-linked sialic acid as a receptor for binding and entry into target cells. The sialic acid is the terminal residue of various types of glycan. There are two major types of alpha2,3-linked sialic acid differing in the penultimate bond: Neu5Acalpha2-3Galbeta1-3GalNAc and Neu5Acalpha2-3Galbeta1-4GlcNAc. In the human airway, while Neu5Acalpha2-3Galbeta1-3GalNAc is present only in alveolar epithelial cells, the Neu5Acalpha2-3Galbeta1-4GlcNAc is expressed in both the upper and lower airway. Previous data showed preferential binding of hemagglutinin from H5N1 highly pathogenic influenza virus to Neu5Acalpha2-3Galbeta1-4GlcNAc. We further show here that suppression of this sialic acid by siRNA against a sialyltransferase, ST3GAL4, can inhibit H5N1 avian influenza virus infection and that this gene is abundantly expressed in human pharynx, trachea and bronchus. These data suggest that the ST3GAL4 gene is responsible for biosynthesis of the viral receptor and may play a crucial role in infection of H5N1 avian influenza virus in humans.
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PMID:Inhibition of H5N1 highly pathogenic influenza virus by suppressing a specific sialyltransferase. 2038 41

In chicken, ST3 beta-galactoside alpha-2, 3-sialyltransferase III (ST3GAL III) is one of the key enzymes participating in the biosynthesis of avian influenza virus receptors. Knowledge about ST3Gal III could increase our understanding of its function in the occurrence and development of avian influenza. To date, no detailed data have been published about the expression pattern and histological distribution of ST3Gal III in chicken. This paper presents data on the nucleotide sequence, mRNA expression pattern and histological distribution of ST3Gal III protein in yellow chicken for the first time. The results show that the nucleotide homology of ST3Gal III among yellow chicken and turkey, chicken, cattle, humans, swine, mouse, rat and chimpanzee was 98%, 92%, 75%, 59%, 70%, 76% and 75%. The relative expression level of ST3Gal III in the heart, kidney and brain of yellow chicken was significantly higher than in other tissues examined for mRNA level (P < 0.05). The histological distribution of ST3Gal III in the heart, liver, spleen, lung, thymus and bursa of Fabricius was determined by immunohistochemical staining using rabbit anti-chicken ST3Gal III IgG prepared by us. Interestingly, the epithelial reticular cells in the immune organs proved to be positive, which may suggest that these cells are important immune cells playing a role in influenza virus infection. The results of this study provide basic data for further research on the functions of ST3Gal III in chicken.
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PMID:The expression pattern and histological distribution of sialyltransferases ST3Gal III in yellow chicken. 2394 96