The expression pattern and histological distribution of sialyltransferases ST3Gal III in yellow chicken.

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.