The full-length sequence of the odorant binding protein 5 gene,HarmOBP5,was obtained from an antennae cDNA library of cotton bollworm,Helicoverpa armigera (Hübner).The cDNA contains a 444 bp open reading frame,...The full-length sequence of the odorant binding protein 5 gene,HarmOBP5,was obtained from an antennae cDNA library of cotton bollworm,Helicoverpa armigera (Hübner).The cDNA contains a 444 bp open reading frame,encoding a protein with 147 amino acids,namely HarmOBP5.HarmOBP5 was expressed in Escherichia coli and the recombinant protein was purified by affinity chromatography.SDS-PAGE and Western blot analysis demonstrated that the purified protein can be used for further investigation of its binding characteristics.Competitive binding assays with 113 odorant chemicals indicated that HarmOBP5 has strong affinity to some special plant volatiles,including (E)-β-farnesene,ethyl butyrate,ethyl heptanoate,and acetic acid 2-methylbutyl ester.Based on three-dimensional (3D) model of AaegOBP1 from Aedes aegypti,a 3D model of HarmOBP5 was predicted.The model revealed that some key binding residues in HarmOBP5 may play important roles in odorant perception of H.armigera.This study provides clues for better understanding physiological functions of OBPs in H.armigera and other insects.展开更多
利用粉纹夜蛾Trichoplusia ni Hbner卵细胞系(Hi-5细胞系)在细胞水平研究了印楝素(azadirachtin)A杀卵活性的毒性机理。以MTT法研究了印楝素A对粉纹夜蛾Hi-5细胞的生长抑制率,结果表明最初两天印楝素A对Hi-5细胞无较明显活性,但...利用粉纹夜蛾Trichoplusia ni Hbner卵细胞系(Hi-5细胞系)在细胞水平研究了印楝素(azadirachtin)A杀卵活性的毒性机理。以MTT法研究了印楝素A对粉纹夜蛾Hi-5细胞的生长抑制率,结果表明最初两天印楝素A对Hi-5细胞无较明显活性,但随后几天抑制率显著增加。用Giemsa染色法对细胞进行染色,观察细胞形态发生的变化,发现:1.25μg/mL印楝素A处理Hi-5细胞1d后,细胞已无法贴壁,形状变圆,接着细胞形态变得极不规则,有凋亡小体出现。用Ho33342染料对Hi-5细胞核DNA染色,通过荧光显微镜观察发现:经印楝素A处理后第1天,部分细胞核染色体发生异常凝聚,此后异常细胞核比例增多,核膜严重破损。以异硫氰酸荧光素(FITC)荧光染料研究了Hi-5细胞的蛋白质含量变化,发现1.25μg/mL印楝素A处理Hi-5细胞1d后,细胞蛋白质指数(DI)为1.070±0.018,至第3dDI值上升到1.912±0.019。分析了印楝素A处理后Hi-5的还原性谷胱甘肽(GSH)的相对含量变化,发现1.25μg/mL处理浓度下,各天处理组GSH抑制率有显著差异。结果显示印楝素A能够抑制Hi-5细胞增殖,影响细胞骨架正常功能,降低细胞活力。展开更多
基金supported by the National Basic Research Program of China(2012CB114104)the National Natural Science Foundation of China(30871640,31071694)+1 种基金the National High-Tech R&D Program of China(2008AA02Z307)the International Cooperation and Exchange Foundation of NSFC-RS of China(31111130203).
文摘The full-length sequence of the odorant binding protein 5 gene,HarmOBP5,was obtained from an antennae cDNA library of cotton bollworm,Helicoverpa armigera (Hübner).The cDNA contains a 444 bp open reading frame,encoding a protein with 147 amino acids,namely HarmOBP5.HarmOBP5 was expressed in Escherichia coli and the recombinant protein was purified by affinity chromatography.SDS-PAGE and Western blot analysis demonstrated that the purified protein can be used for further investigation of its binding characteristics.Competitive binding assays with 113 odorant chemicals indicated that HarmOBP5 has strong affinity to some special plant volatiles,including (E)-β-farnesene,ethyl butyrate,ethyl heptanoate,and acetic acid 2-methylbutyl ester.Based on three-dimensional (3D) model of AaegOBP1 from Aedes aegypti,a 3D model of HarmOBP5 was predicted.The model revealed that some key binding residues in HarmOBP5 may play important roles in odorant perception of H.armigera.This study provides clues for better understanding physiological functions of OBPs in H.armigera and other insects.
文摘利用粉纹夜蛾Trichoplusia ni Hbner卵细胞系(Hi-5细胞系)在细胞水平研究了印楝素(azadirachtin)A杀卵活性的毒性机理。以MTT法研究了印楝素A对粉纹夜蛾Hi-5细胞的生长抑制率,结果表明最初两天印楝素A对Hi-5细胞无较明显活性,但随后几天抑制率显著增加。用Giemsa染色法对细胞进行染色,观察细胞形态发生的变化,发现:1.25μg/mL印楝素A处理Hi-5细胞1d后,细胞已无法贴壁,形状变圆,接着细胞形态变得极不规则,有凋亡小体出现。用Ho33342染料对Hi-5细胞核DNA染色,通过荧光显微镜观察发现:经印楝素A处理后第1天,部分细胞核染色体发生异常凝聚,此后异常细胞核比例增多,核膜严重破损。以异硫氰酸荧光素(FITC)荧光染料研究了Hi-5细胞的蛋白质含量变化,发现1.25μg/mL印楝素A处理Hi-5细胞1d后,细胞蛋白质指数(DI)为1.070±0.018,至第3dDI值上升到1.912±0.019。分析了印楝素A处理后Hi-5的还原性谷胱甘肽(GSH)的相对含量变化,发现1.25μg/mL处理浓度下,各天处理组GSH抑制率有显著差异。结果显示印楝素A能够抑制Hi-5细胞增殖,影响细胞骨架正常功能,降低细胞活力。