Insects receive a variety of chemical signals from the environment. Chemosensory protein (CSP) is one of the olfactory proteins that can accommodate a variety of small molecules and have the ability to bind to lipophilic compounds, transmitting nonvolatile odor molecules and chemical stimuli to target cells. To understand the correlation between the insect olfactory system and environment, we identified four antennae-expressed SlituCSP genes and investigated their expression profiles after treatment with different temperatures, starvation and three commonly used pesticides : chlorpyrifos , emamectin benzoate and fipronil . The transcriptions of four SlituCSP genes are affected by pesticide treatment and less affected by starvation and different temperatures. To further understand the molecular function of CSPs and their correlation with pesticides, we expressed and purified four SlituCSPs and assayed their binding ability with pesticides. The binding of four SlituCSPs with three pesticides were determined using a fluorescence competitive binding assay. We found direct binding between CSPs and pesticides, especially between SlituCSP18 and chlorpyrifos/fipronil and between SlituCSP6 and all three pesticides. The high binding affinity with pesticides and the significant down-regulation of SlituCSP18 by chlorpyrifos suggests that SlituCSP18 is more sensitive to pesticide treatment and may play an important role in mediating the interaction of the olfactory system and the pesticide. This study can help us understand the role of CSP proteins in the adaption of S. litura to the environment.
Xing Juan Chen,Guang Lei Yang,Xiao Dong Xu,Jin Jin Sheng,Jun Shen,Hong Xing Dong
Five β-cyclodextrin (β-CD) derivatives bearing substituted phenylcarbamate/3-(triethoxysilyl)propylcarbamate groups at the 2-, 3-, and 6-positions of glucose unit and another five derivatives containing benzoate at the 2-position and substituted phenylcarbamate/3-(triethoxysilyl)propylcarbamate groups at the 3- and 6-positions were synthesized using the regioselective esterification method. The obtained β-CD derivatives were efficiently immobilized onto the silica gel through the intermolecular polycondensation of a small amount of the triethoxysilyl groups, which were used as the chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC). The chiral separation properties of these CSPs were evaluated under the normal-phase HPLC. The effects of solvent polarity and the side chain structures of β-CD derivatives on the chiral recognition ability of the immobilized CSPs were investigated. Among these β-CD derivative CSPs, 2,3,6-tris(3,5-dichlorophenylcarbamate)-β-CD CSP showed a relatively high chiral recognition ability for the studied racemates. The regioselective esterification at the 2-position of glucose unit in the β-CD decreased the chiral recognition ability at the same conditions. For some racemates, the β-CD derivative CSPs showed chiral recognition abilities comparable or better to some chemical bonded β-CD derivative CSPs and 3,5-dichloro- and 3,5-dimethylphenylcarbamates of cellulose and amylose CSPs.
危险品化学品经营许可证（带存储）