Molecular cloning and characterization of a beta-1,3-glucan recognition protein from Plutella xylostella (L.)

摘要

The beta-glucan recognition proteins (beta GRPs) play a significant role as important pattern recognition proteins (PRPs) for recognizing conserved surface determinants of pathogens and trigger complex signaling pathways in invertebrates. In the present study, a full-length cDNA 1793 bp encoding 479 amino acids and beta GRP1 was obtained from Plutella xylostella by reverse transcription PCR (RT-PCR) (designed as P x beta GRP1) which showed significant similarities with other insect's beta GRPs. The transcription level was constitutively expressed and upregulated by microbial induction in all life stages of P. xylostella. Tissue distribution showed P x beta GRP1 to be mainly expressed in fat body as detected by quantitative real-time PCR (qRT-PCR) and immunohistochemistry. Subsequent to knock down the P x beta GRP1 expression and the transcripts of Toll-like receptor, cecropin 1 and cecropin 2 decreased in P. xylostella. Meanwhile, the bacterial colonies increased and the expression of four AMP genes decreased on injection of anti-P x beta GRP1 into Bombyx mori. The results demonstrated that P x beta GRP1 can play a vital role in response to the expression of AMP genes in P. xylostella.