Cloning, Expression And Bioinformatic Analysis Of The LSP-2Gene In The Onion Maggot, Delia Antiqua

Diapause is genetic and environmental work together, causing a series of changesin genes and proteins encoding process of the insect, leading to the insect growth,development and reproduction of stagnation a life phenomenon; It is an importantecological countermeasures, can help insects against bad environmental, maintain andindividual survival, continue race development. The characteristics of diapause ismetabolic activity significantly reduced, developmental stagnation. Storage protein is ahigh abundance of hexamer protein. It plays an important role in the process of insectmetamorphosis. Storage proteins as a repository of protein and amino acids involved inthe insect epidermis formation and hardening, as a carrier of other substancestransported to the target cells. Insect larvae serum protein belong to storage protein. Inthe process of insect metamorphosis, such as molting, diapause, adult metamorphosisand egg shell formation, the larval serum protein plays an important role for the insectstorage and metabolism of amino acids. The growth and development of the insectscan not be separated in the regulation of hormone. Hormone involved in the regulationof storage protein. In insect pupation, ecdysteroids by the larval serum protein in thefat body membrane binding sites, be specific to selective absorption. Juvenile hormonecan inhibit the synthesis of storage proteins in the transcriptional level.Delia antique is anthomyiidae of diptera, with winter diapause and summerdiapause. In this study, the main content was cloned of the LSP-2gene in the onionmaggot, and bioinformatic analysis of this gene and the deduced protein sequence.Meanwhile, this study analyzed the expression of LSP-2gene in diapause with thesemi-quantitative PCR and real-time quantitative PCR. The results are as follows.①The full-length cDNA is2203bp long, with an open reading frame (ORF) of2103bp, encoding a protein of701amino acids. It calculated molecular weight is80.5kDa, and theoretical isolectric point is5.87. It is stable, soluble protein of thehydrophilic. By the signal peptide and transmembrane region prediction show that,LSP-2protein of onion maggot has a signal peptide (between1～20aa) and a strongtransmembrane helix(between17～33aa).By the phosphorylation sites analysis showthat, LSP-2protein of onion maggot have a conserved phosphorylation sites sequences TSLRDPLFY and a conservative glycosylation sites sequences ADKDFLVKQK. Bythe domain prediction analysis show that, LSP-2protein of onion maggot containsthree domains with Hemocyanin_N,Hemocyanin_M and Hemocyanin_C. By theamino acid sequence alignment analysis show that, LSP-2protein of onion maggot hasthe highest similarity with Calliphora vicina and the closest relationship with otherDiptera evolutionarily.②The relative expression of the LSP-2gene of the onion maggot during thediapause pupae and the non-diapause pupae was analyzed. The LSP-2gene of onionmaggot transcription changed significantly during the non-diapause, however, it doesnot obvious during wenter diapause. The LSP-2gene of onion maggot transcriptionwas up-regulated in pre-diapause and the end of diapause, However, it wasdown-regulated in summer diapause. These results suggested that the LSP-2gene ofonion maggot may play an important role in the development process after diapause.