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61.
载球孢白僵菌松毛虫赤眼蜂能够显著提高对亚洲玉米螟的防控效果,为了明确其对亚洲玉米螟卵期及幼虫期可持续防控的作用机理,采用松毛虫赤眼蜂吸附绿色荧光蛋白(GFP)标记的球孢白僵菌分生孢子,进行赤眼蜂载菌情况,以及亚洲玉米螟卵和幼虫的寄生、侵染过程观察。结果表明,赤眼蜂羽化后能够吸附柞蚕卵表面粘附的白僵菌分生孢子,并将其携带至亚洲玉米螟卵块表面,并吸附于未被赤眼蜂寄生的亚洲玉米螟卵孵化的幼虫体表,实现侵染并致死,幼虫带菌率达60.00%,网室内杀虫生物测定僵虫率达27.00%。本研究表明,载菌赤眼蜂在提高杀虫效率的同时实现害虫可持续防控,该方法为其他载菌天敌的应用提供了依据。  相似文献   
62.
Th IPK2 is an inositol polyphosphate kinase gene cloned from Thellungiella halophila that participates in diverse cellular processes. Drought is a major limiting factor in wheat(Triticum aestivum L.) production. The present study investigated whether the application of the Th IPK2 gene could increase the drought resistance of transgenic wheat. The codon-optimized Th IPK2 gene was transferred into common wheat through Agrobacterium-mediated transformation driven by either a constitutive maize ubiquitin promoter or a stress-inducible rd29 A promoter from Arabidopsis. Molecular characterization confirmed the presence of the foreign gene in the transformed plants. The transgenic expression of Th IPK2 in wheat led to significantly improve drought tolerance compared to that observed in control plants. Compared to the wild type(WT) plants, the transgenic plants showed higher seed germination rates, better developed root systems, a higher relative water content(RWC) and total soluble sugar content, and less cell membrane damage under drought stress conditions. The expression profiles showed different expression patterns with the use of different promoters. The codon-optimized Th IPK2 gene is a candidate gene to enhance wheat drought stress tolerance by genetic engineering.  相似文献   
63.
【目的】建立水稻叶片蛋白的多反应监测(MRM)质谱绝对定量方法。【方法】水稻叶片蛋白经含1.0%十二烷基硫酸钠(SDS)的磷酸盐(PBS)缓冲液提取,丙酮沉淀除杂纯化、胰蛋白酶消化,酶解液经液相色谱分离,MRM质谱监测,外标法定量。【结果】向提取缓冲液中加入1.0%SDS可增强水稻叶片中16种靶蛋白和总蛋白质的提取效果;不同有机试剂处理,总蛋白质沉淀量存在显著差异(P<0.05),沉淀能力从强到弱依次为乙腈>丙酮>异丙醇>甲醇>乙醇;对于16种目标蛋白,总体以丙酮沉淀效果最好,其次是异丙醇和乙腈,甲醇和乙醇效果较差。该方法线性范围均达到3个数量级,定量限为0.1~2.5 nmol/L,灌浆期16种水稻叶片蛋白质含量为6.0~2818.1μg/g,相对标准偏差均小于14%。【结论】SDS可显著提高水稻叶片蛋白提取效果,采用丙酮或乙腈可获得较好的蛋白沉淀效果,但不同蛋白质略有差异。结合MRM质谱监测技术可实现水稻叶片蛋白的绝对定量,方法线性范围宽、敏度高、重复性好。  相似文献   
64.
通过生物信息学的方法对玉米木质形成素类阿拉伯半乳糖蛋白(xylogen-like arabinogalactan proteins,XYLPs)基因家族的表达模式和蛋白结构进行了分析。ZmXYLPs基因家族成员在染色体上的分布具有一定的偏好性。基因复制事件不仅在基因家族成员数量的扩张和进化中发挥重要作用,同时还可能引起基因表达部位的扩张。根据ZmXYLPs蛋白结构特点,可将其分为两大类。其中仅ZmXYLP10/13/14蛋白存在N连接的糖修饰位点,其余ZmXYLPs蛋白均为O连接糖修饰位点。结果显示,玉米ZmXYLPs的生物学功能可能与其糖基侧链有关,并且其作用并不局限于维管组织发生过程,可能也参与生殖发育过程。  相似文献   
65.
AIM: To investigate the expression and roles of family with sequence similarity 3, member C (FAM3C) in oral squamous-cell carcinoma cells. METHODS: The mRNA and protein expression levels of FAM3C in dysplastic oral keratinocyte (DOK) and oral squamous-cell carcinoma WSU-HN6 cells were detected by RT-qPCR and Western blot. The WSU-HN6 cells were treated with siFAM3C or FAM3C antibody. After 24, 48 and 72 h, the viability of WSU-HN6 cells was measured by CCK-8 assay, and the activation of protein kinase B (Akt) was detected by Western blot. Adenovirus was used to mediate over-expression of FAM3C in the DOK cells. The DOK cell viability was measured by CCK-8 assay after adenovirus infection for 24, 48 and 72 h, and the activation of Akt was detected by Western blot. RESULTS: Compared with the DOK cells, the mRNA and protein levels of FAM3C were significantly increased in the WSU-HN6 cells (P<0.05). The viability of WSU-HN6 cells transfected with siFAM3C was significantly inhibited at 48 h and 72 h (P<0.05). siFAM3C treatment inhibited the activation of Akt (P<0.05). FAM3C antibody treatment also suppressed the viability of the WSU-HN6 cells at 48 h and 72 h and the activation of Akt (P<0.05). Over-expression of FAM3C in the DOK cells promoted the cell viability at 48 h and 72 h and activated Akt (P<0.05). CONCLUSION: FAM3C might promote oral squamous-cell carcinoma cell growth by activating Akt.  相似文献   
66.
An 8‐wk feeding trial was conducted to evaluate the effects of varying dietary protein and lipid levels with different protein‐to‐energy (P/E) ratios on growth, feed utilization, and plasma biochemical parameters of Sinocyclocheilus graham. Nine experimental diets were formulated to contain three protein levels (35, 40, and 45%), and each with three lipid levels (4, 8, and 12%), to produce a range of P/E ratios from 71.31 to 98.64 mg protein/kcal. Each diet was randomly assigned to triplicate groups of 25 fish. Fish grew best when fed the diet containing 45% protein and 12% lipid. However, fish fed the diet with 40% protein and 8% lipid had similar weight gain and specific growth rate as those fed the above diet but showed relatively better feed conversion ratio, protein efficiency ratio, and protein and energy retentions. Additionally, plasma total amino acids and blood urea nitrogen contents and γ‐glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase activities in fish fed the diet containing 40% protein and 8% lipid were relatively low among the dietary treatments. These results may indicate that a diet containing 40% protein and 8% lipid with P/E ratio of 84.05 mg protein/kcal would be suitable for the optimal growth, feed utilization, and health of S. graham.  相似文献   
67.
AIM:To observe whether selective inhibition of endothelin receptor A (ETRA) improves white matter lesions (WMLs), and explore the mechanism. METHODS:Sprague-Dawley rats (n=33) were randomly divided into sham operation group (n=9), treatment group[stroke-prone renovascular hypertensive rats-modified 2 vessel occlusion (RHRSP-modified 2VO) + ambrisentan (n=12)] and placebo group[RHRSP-modified 2VO + vehicle (n=12)]. Drug and vehicle administration was performed from 17th to 20th week and monitoring of systolic arterial pressure was performed weekly. Morris water maze test was conducted to evaluate the function of cognition. The protein levels of endothelin-1 (ET-1) in the cortex, corpus callosum and caudate putamen were quantitatively analyzed respectively. The severity of WMLs and the relationship between ET-1 and vessels were observed by the method of histopathology. RESULTS:The difference of systolic arterial pressure between treatment group and placebo group was not significant. The animals in treatment group exhibited shorter escape latency (P<0.05), more times of crossing platform (P<0.05), lower level of ET-1 in corpus callosum and caudate putamen (P<0.05), respectively, improved WMLs severity (P<0.05) and lower binding level of ET-1 to vessels compared with the placebo group. CONCLUSION:Selective inhibition of endothelin receptor A improves the severity of WMLs and ameliorates the cognitive function.  相似文献   
68.
CAO Rui-ping  WANG Jiao  WANG Ce 《园艺学报》2018,34(6):1061-1066
AIM: To investigate the role of zerumbone (ZER) in 1-methyl-4-phenylpyridinium (MPP+)-induced cytotoxicity of human neuroblastoma SH-SY5Y cells. METHODS: Human neuroblastoma SH-SY5Y cells were cultured in vitro and the protective effect of ZER against MPP+-induced cytotoxicity was measured by CCK-8 assay. Flow cytometry was used to determine the apoptosis and reactive oxygen species (ROS). The expression of Parkinson disease protein 7 (PARK7) was knocked-down by using PARK7-specific short hairpin RNA (shRNA). The protein levels of PARK7, nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were determined by Western blot. RESULTS: MMP+ remarkably reduced the cell viability in a dose-dependent and time-dependent manner. The SH-SY5Y cell injury model was established by treatment with MPP+ at 600 μmol/L for 24 h. ZER up-regulated the protein levels of PARK7 and Nrf2 (P<0.05), alleviated apoptosis (P<0.05), and reduced ROS production (P<0.05) in the SH-SY5Y cell injury model. Meanwhile, N-acetyl-L-cysteine (NAC) had the similar functions. Moreover, significant reductions in the protein levels of Nrf2 and HO-1 (P<0.05), and obvious increases in apoptosis (P<0.05) and ROS level (P<0.05) were demonstrated in PARK7-knockdown cells. CONCLUSION: ZER protects SH-SY5Y cells against MPP+-induced cytotoxi-city, which may be related to activation of PARK7/Nrf2/HO-1 pathway, and subsequent attenuation of oxidative stress and apoptosis.  相似文献   
69.
昆虫嗅觉相关蛋白的研究进展   总被引:2,自引:0,他引:2  
昆虫对自然环境中复杂化学信号的识别多依赖于其灵敏的嗅觉系统,选择寄主、觅食、寻找配偶等行为的发生都以嗅觉识别为基础,而完成嗅觉识别还需要多种嗅觉相关蛋白的参与。嗅觉相关蛋白主要包括6种,即气味结合蛋白、化学感受蛋白、气味受体、感觉神经元膜蛋白、离子型受体和气味降解酶。不同种类和性别的昆虫中,嗅觉蛋白的种类、数量和分布各不相同。由于嗅觉蛋白在昆虫识别外界气味分子中的重要作用,国内外近年来对其展开了广泛、深入的研究。本文从几种嗅觉相关蛋白的生化特性、分子结构、生理功能、分布表达部位和研究概况等角度,较详细地综述了近年来国内外昆虫嗅觉相关蛋白的研究进展。  相似文献   
70.
This study compares the effect of food type (formulated diet vs. natural food) and fish size on protein and energy utilization efficiencies for growth in common sole, Solea solea (L.). Replicate groups of common sole (mean initial body weight ± SD was 45.7 g ± 2.1 and 111.2 g ± 4.2) received the diets at five (natural feed) or four (formulated diet) feeding levels. The protein utilization efficiency for growth (kgCP) was higher (> 0.001) in common sole fed ragworms than in common sole fed the formulated diet (respectively, 0.40 and 0.31). Likewise, the energy utilization efficiency for growth (kgGE) was higher (= 0.001) in common sole fed ragworms than in common sole fed the formulated diet (respectively, 0.57 and 0.33). The protein maintenance requirement was not different between food types (= 0.64) or fish size (= 0.41) being on average 0.82 g kg?0.8 day?1. The energy maintenance requirement was not different between food type (= 0.390) but differed between fish size (= 0.036). The gross energy maintenance requirement of small common sole was 35 kJ g?0.8 day?1. The gross energy maintenance requirement of large common sole was 25 kJ g?0.8 day?1. In conclusion, the low growth of common sole fed formulated diets was related to reduced feed utilization.  相似文献   
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