Molecular Characterization And Identification Of C-type Lectin (CTL) In Rhynchophoru Ferrugineus Olivier

Insect's innate immunity depends on a variety of defense responses for the recognition of invading pathogens.Pathogen recognition involves particular proteins known as pattern recognition receptors(PRRs).These PRRs interact with pathogen associated molecular patterns(PAMPs)present on the surface of pathogens to distinguish between self and non-self.C-type lectins(CTLs)belong to a super family of PPRs which are involved in insect immunity and defense mechanism.Rhynchophorus ferrugineus Olivier(Coleoptera;Curculionidae)is a devastating pest of palm cultivations in China.Although studies on R.ferrugineus immune mechanism and host defense have been conducted,however,the role of CTL in immune responses of R.ferrugineus remains elusive.Here,we reported the molecular characterization and identification of a single-CRD CTL,named C-type lectin(RfCTL)from R.ferrugineus.The open reading frame(ORF)of CTL is 226 bp,which encodes a putative protein of 170 amino acids.Transcript expression analysis revealed that RfCTL were highly expressed in immune-related tissues i.e.hemolymph and fat body.The abundance of RfCTL in gut and fat body was dramatically increased upon Staphylococcus aureus and Escherichia coli bacterial challenges,suggesting a role in defense against gram positive and gram negative bacterial infection.Taken together,we inferred that RfCTL might be involved in the immune defense of R.ferrugineus and established a solid foundation for future studies on R.ferrugineus CTL domain proteins for better understanding of insect immunity.