Bombyx mori triose-phosphate transporter protein inhibits Bombyx mori nucleopolyhedrovirus infection by reducing the cell glycolysis pathway

Bombyx mori triose-phosphate transporter protein (BmTPT) is a member of the solute carrier (SLC) family. Its main function is to transport triose phosphate between intracellular and extracellular. In this study, BmTPT was cloned and characterised from the fat body of the silkworm Bombyx mori, resulting in an open reading frame (ORF) with a full length of 936 bp, which can encode 311 amino acid residues and has eight transmembrane structural domains. BmTPT was distributed throughout the cell and deposited the most in the nucleus, and is expressed in all tissues of Bombyx mori. Bombyx mori nucleopolyhedrovirus (BmNPV) infection significantly up-regulated BmTPT expression in immune tissue fat bodies. In addition, overexpression of BmTPT significantly inhibited BmNPV infection and markedly reduced the expression of enzymes related to the cellular glycolytic pathway; on the contrary, down-regulation of BmTPT expression by RNA interference resulted in robust replication of BmNPV and a significant increase in the expression of enzymes related to the cellular glycolytic pathway. This is the first report that BmTPT has antiviral effect in silkworm, and also could result in a lack of energy and raw materials for BmNPV replication and infection through down-regulation of the cellular glycolytic pathway.