β-Galactoside α 2-6 Sialyltransferase gene expression in Bombyx mori tissues

Bombyx mori is an important insect due to its genome, homology to humans, and ease of growth. Sialylation has been reported in some insects, but sialic acid biosynthesis cannot be observed in these insects. Sialic acids are negatively charged nine carbon sugars located terminally on glycoconjugates. Sialylation, which occurs after translation and is regulated by enzymes, has been studied in prokaryotes, dueterostomes, and protostomes. One of the enyzme that important for sialylation is sialyltransferases. This enyzme play role at linked sialic acid to glycoconjugates. In this study we investigated sialyltransferase (β-Galactoside α-2,6-Sialyltransferase I) gene expression in tissues of B. mori. B. mori larvae, which were fed with fresh mulberry leaves since hatching, were divided into two groups; the control group, which continued to be fed with fresh mulberry leaves in the 5th instar (last instar) and the treatment group, which was fed with mulberry leaves treated with sialic acid solution. Midgut, fat body, hemocyte, ovary and testicular tissues were dissected and gene expressions were examined with Real-Time PCR. The expression level observed in every tissue but increase seen in only fat body. Fat body is very important tissue for insect, plays a fundamental role in immunity, endocrine and detoxification processes. The reason for the highest gene expression in fat body can be attributed to the similarities in the functions of fat body and sialic acid and their roles in insects.