Learning Experience Influence The Expression Of The Odorant Binding Protein In Scleroderma Sichuanensis Xiao

Scleroderma sichuanensis Xiao, belong to Bethylidae, Scleroderma, is a variety of borer pests parasitic natural enemy insects, which has important value in biological control. Insects can perceive in the air volatile substances so as to guide the behavior include two important aspects:one is the host plant volatiles including chemical fingerprints from multiple odor substance, and the other is an insect with structure and recognition mechanism which adapts with it. Only to study the two aspects in depth, can be very good applied to the practice of pest control. In recent years, researching the smell of the material behavior pattern of insects is more, but study of the insect odorant binding protein and the relationship between odor identification is less.Researching on parasitic wasps are muchi less. Therefore, we use the Y-type behavior to test at the behavioral response of different ages of S. sichuanensis which treated with Batocera horsfieldi to mixture of excrement and sawdust. In order to research the learning effect of S. Sichuanensis of B. horsfieldi to mixture of excrement and sawdust; then according to cDNA sequences of odorant binding protein in Sclerodermus guani Xiao et Wu, get two odorant binding protein cDNA fragment of S. sichuanensis by RT-PCR method and clone them;we use SYBR Green I dye method to get odorant binding protein gene expression profiles of S. sichuanensis about different parts and the different age of experience by Real-Time PCR wirh relative quantitative method which compare with the Ct value,in order to study on the regulation of gene expression. Preliminary exploration of the effect between expression of the gene and odorant binding protein of S. sichuanensis learning effect. the main research results are as follows:1. Study effect of different ages of S. sichuanensis with treatment with B. horsfieldi to mixture of excrement and sawdust.compared with no experience of treatment, treatment with B. horsfieldi to mixture of excrement and sawdust, the selection rate of the smell were improved. S. Sichuanensis in the early emergence and adult (1,2 day-old), the learning effect to B. horsfieldi to mixture of excrement and sawdut increases gradually, learning effect is strongest in the second day after eclosion. In the 4th-10th days after emergence, learning effect weakens. In twelfth days after eclosion, learning effect significantly enhances.2. Molecular Cloning and Sequence Analysis of Genes Encoding OBPs in the Antenna of S. sichuanensis.Two pairs of primers were designed based on the comparison of Sgua-OBP1 and Sgua-OBP2 gene sequences of S. guani antenna. Cloning two new cDNAs, named OBP1 and OBP2, encoding odorant binding protein Ssic-OBP1 and Ssic-OBP2 from S. sichuanensis(GenBank Number:KM924438 and KM924439. Sequencing and structural analysis showed that the length of Ssic-OBP1 ORF was 401 bp,133 amino acid residues were encoded.The length of Ssic-OBP2 ORF was 420 bp,139 amino acid residues were encoded. Both of Ssic-OBP1 and Ssic-OBP2 were Acidic Protein.The predicted MW of the former was 14.4 kD, and the latter was 15.7 kD. There are six conservative Cys locus in the sequence and is mainly composed of 6 alpha helix, which is the typical characteristic of OBPs. Multiple sequence alignment and phylogenetic tree analysis show that the deduced amino acid sequence of Ssic-OBP1 and Sgua-OBPl has 98% similarity, and the similarity with other insect which distantly related to is less than 49%. The similarity of Ssic-OBP2 and Sgua-OBP2 up to 99%, the similarity with other insect which distantly related to is less than 39%. To a certain extent on the closer genetic relationship, odorant binding protein amino acid sequence similarity is high.3. Expression of Ssic-OBP1 and Ssic-OBP2 in different tissues ofS.sichuanensisTwo types of odorant binding proteins are systemic distribution of protein. The expression of Ssic-OBP1 in S. sichuanensis antenna has high abundance and low abundance expression in other tissues (such as head, thorax, abdomen, leg). The expression of Ssic-OBPl in S. sichuanensis antenna has high abundance and expressed in low abundance in thorax, abdomen and leg, In the head expression less than antenna but more than that in other tissues.4. Transcriptional expression of OBPs gene of S. sichuanensis in different age and experience.Two kinds of OBPs in head and antennae which not yet experienced the smell of B. horsfieldi to mixture of excrement and sawdut, with the increase of age after emergence, the expression quantity changed little, and OBPs which experienced the smell is combined with the egg white,in 1st,2nd days after emergence was gradually increased to the maximum. Then the expression of day 4th after emergence amount reduced sharply, until 10th after emergence the expression is low abundance and stable, and a sharp rise in twelfth days.comparing the expression levels of two kinds of OBPs in S. sichuanensis with different treatment methods, the expression of Ssic-OBP1 and Ssic-OBP2 are increased after experienced the smell of B. horsfieldi to mixture of excrement and sawdust These two proteins may be general odorant binding proteins (GOBPs), which are a major role in the host volatile odor, and play an important role in host searching process. Two kinds of odorant binding protein may combine with some kind of specific substances in B. horsfieldi to mixture of excrement and sawdust in volatile matter or a species specificity, resulting in increased the expression of the corresponding protein after experienced the smell.The expression of two proteins and S. sichuanensis experience learning effect have the same change trend after experienced the same smell. The learning effect which is bad or good may be related to the number of the two OBPs.