Identification and subcellular localization analysis of membrane protein Ycf 1 in the microsporidian .

Microsporidia are obligate intracellular parasites that can infect a wide range of vertebrates and invertebrates including humans and insects, such as silkworm and bees. The microsporidium can cause pebrine in , which is the most destructive disease in the sericulture industry. Although membrane proteins are involved in a wide range of cellular functions and part of many important metabolic pathways, there are rare reports about the membrane proteins of microsporidia up to now. We screened a putative membrane protein Ycf 1 from the midgut transcriptome of the -infected silkworm. Gene cloning and bioinformatics analysis showed that the gene contains a complete open reading frame (ORF) of 969 bp in length encoding a 322 amino acid polypeptide that has one signal peptide and one transmembrane domain. Indirect immunofluorescence results showed that Ycf 1 protein is distributed on the plasma membrane. Expression pattern analysis showed that the gene expressed in all developmental stages of . Knockdown of the gene by RNAi effectively inhibited the proliferation of . These results indicated that Ycf 1 is a membrane protein and plays an important role in the life cycle of .