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991.
Cysteine‐rich secretory protein‐3 (CRISP‐3) and some of its nonsynonymous polymorphism have been related to the fertility and freezability of stallion semen; however, the role of the CRISP‐3 gene and its seminal plasma protein in the raw semen quality is still unknown. The aim of this study was to evaluate the relationship of CRISP‐3 with semen quality in stallions. DNA was obtained from blood samples of 100 stallions, from which 30 stallions were randomly selected to obtain 60 ejaculates. Through PCR amplification and sequencing, the variation of four nonsynonymous SNPs from CRISP‐3 was identified and haplotypes were derived. Semen quality was assessed through the total motility (MOT), sperm vitality (SV), normal morphology (NM), functional integrity of membrane (MI) and a seminal quality index (SQi). CRISP‐3 protein content of seminal plasma (SP) was determined by ELISA. The effect of the genotype, the haplotype and the concentration of the CRISP‐3 protein on the seminal quality were evaluated through generalized linear models and linear regression analyses. Homozygous genotypes for SNP1, SNP2 and SNP3 and the heterozygous genotype for SNP4 showed a positive effect on seminal quality. Different haplotypes with positive effect on MOT, SV, NM, MI and SQi were identified. The allelic substitution analysis resulted in positive regression coefficients for MOT (SNP2) and MI (SNP2 and SNP3). A high level of CRISP‐3 resulted in a higher MOT and SQi. It is concluded that the quality of stallion semen is influenced by the genotype of CRISP‐3 and the concentration of CRISP‐3 protein in SP.  相似文献   
992.
Serum amyloid A (SAA) is the major acute phase protein in horses. It is produced during the acute phase response (APR), a nonspecific systemic reaction to any type of tissue injury. In the blood of healthy horses, SAA concentration is very low, but it increases dramatically with inflammation. Due to the short half-life of SAA, changes in its concentration in blood closely reflect the onset of inflammation and, therefore, measurement of SAA useful in the diagnosis and monitoring of disease and response to treatment. Increases in SAA concentration have been described in equine digestive, reproductive and respiratory diseases and following surgical procedures. Moreover, SAA has proven useful for detection of some subclinical pathologies that can disturb training and competing in equine athletes. Increasing availability of diagnostic tests for both laboratory and field use adds to SAA's applicability as a reliable indicator of horses’ health status. This review article presents the current information on changes in SAA concentrations in the blood of healthy and diseased horses, focussing on clinical application of this biomarker.  相似文献   
993.
The present study identified few potential proteins in the spermatozoa of buffalo bulls that can be used as an aid in fertility determination through comparative proteomics. The sperm proteome of high‐fertile buffalo bulls was compared with that of low‐fertile buffalo bulls using two‐dimensional difference gel electrophoresis (2D‐DIGE), and the differentially expressed proteins were identified through mass spectrometric method. The protein interaction network and the functional bioinformatics analysis of differentially expressed proteins were also carried out. In the spermatozoa of high‐fertile bulls, 10 proteins were found overexpressed and 15 proteins were underexpressed at the level of twofold or more (p ≤ 0.05). The proteins overexpressed in high‐fertile spermatozoa were PDZD8, GTF2F2, ZNF397, KIZ, LOH12CR1, ACRBP, PRSS37, CYP11B2, F13A1 and SPO11, whereas those overexpressed in low‐fertile spermatozoa were MT1A, ATP5F1, CS, TCRB, PRODH2, HARS, IDH3A, SRPK3, Uncharacterized protein C9orf9 homolog isoform X4, TUBB2B, GPR4, PMP2, CTSL1, TPPP2 and EGFL6. The differential expression ranged from 2.0‐ to 6.1‐fold between the two groups, where CYP11B2 was high abundant in high‐fertile spermatozoa and MT1A was highly abundant in low‐fertile spermatozoa. Most of the proteins overexpressed in low‐fertile spermatozoa were related to energy metabolism and capacitation factors, pointing out the possible role of pre‐mature capacitation and cryo‐damages in reducing the fertility of cryopreserved buffalo spermatozoa.  相似文献   
994.
995.
为表达具有天然构象的蓝舌病病毒血清1型(BTV1)主要结构蛋白VP2、VP3、VP5和VP7,研制针对流行于我国的BTV1型毒株的病毒样颗粒(virus-like particles,VLP)疫苗提供基础,将编码BTV1 VP2和VP5蛋白的基因分别克隆到双表达载体pFastBacDual的启动子pPH和pP10下游,构建重组质粒pFastBacDualBTV1-VP2-VP5,将重组质粒转化DH10Bac感受态细胞,获得重组穿梭质粒rBacmidBTV1-VP2-VP5,转染Sf9昆虫细胞,获得重组杆状病毒rBacBTV1-VP2-VP5;按照同样策略,制备重组杆状病毒rBacBTV1-VP3-VP7。使用兔抗BTV1-VP5蛋白多克隆抗体和鼠抗BTV-VP7蛋白单克隆抗体,分别对rBacBTV1-VP2-VP5和rBacBTV1-VP3-VP7感染的Sf9细胞进行间接免疫荧光试验(IFA)检测,结果病毒感染细胞可见特异性荧光出现;使用兔抗BTV1-VP2蛋白多克隆抗体和兔抗BTV1-VP3蛋白多克隆抗体,分别对rBacBTV1-VP2-VP5和r BacBTV1-VP3-VP7感染的Sf9细胞进行Western-blot检测,可见相对分子质量约100 kDa左右的条带,大小与预期相符。IFA检测和Western Blot检测结果显示,BTV1 VP2、VP3、VP5和VP7蛋白均得以表达,且具有良好的反应原性。  相似文献   
996.
口蹄疫疫苗非抗原蛋白对146S抗原免疫效果的影响   总被引:1,自引:1,他引:0  
为探究非抗原蛋白对口蹄疫病毒A型(FMDV-A) 146S抗原免疫效果的影响,本研究以小鼠和猪为试验动物,分别制备5组小鼠注射用样品:A组(3μg 146S抗原)、B组(3μg 146S抗原+25μg非抗原蛋白)、C组(3μg 146S抗原+50μg非抗原蛋白)、D组(3μg 146S抗原+100μg非抗原蛋白)及E组(空白对照,PBS);同时制备4组猪注射用样品:A组(18μg 146S抗原)、B组(18μg 146S抗原+400μg非抗原蛋白)、C(18μg 146S抗原+4 000μg非抗原蛋白)及D组(空白对照,PBS)。免疫接种试验动物后,通过淋巴细胞增殖试验及实时荧光定量PCR评价比较不同疫苗样品组小鼠产生的细胞免疫应答水平,同时通过液相阻断ELISA方法检测、评价各试验组动物(小鼠和猪)产生的体液免疫应答水平。小鼠试验结果显示,在免疫后3个检测时间点内,4个试验组中C组的平均抗体水平最高,平均抗体效价分别为4.13、5.83和5.50,而D组的抗体水平最低,平均抗体效价分别为3.46、5.16和4.46;C组细胞增殖能力及Th-1型细胞因子IL-6、IFN-β和TNF-αmRNA表达量均高于其他组。猪试验结果显示,A组和B组间平均抗体水平差异不显著(P>0.05),但A组和B组的平均抗体效价均极显著高于C组(P<0.01)。综合上述结果表明,一定范围内少量非抗原蛋白对FMDV-A 146S抗原的免疫效果没有影响,而高浓度的非抗原蛋白则抑制FMDV-A 146S抗原的免疫效果。  相似文献   
997.
The objective of this study was to investigate the reason for variation in the virulence of white spot syndrome virus (WSSV) from different shrimp farms in the Southeast coast of India. Six isolates of WSSV from farms experiencing outbreaks (virulent WSSV; vWSSV) and three isolates of WSSV from farms that had infected shrimps but no outbreaks (non‐virulent WSSV; nvWSSV) were collected from different farms in the Southeast coast of India. The sampled animals were all positive for WSSV by first‐step PCR. The viral isolates were compared using histopathology, electron microscopy, SDS‐PAGE analysis of viral structural proteins, an in vivo infectivity experiment and sequence comparison of major structural protein VP28; there were no differences between isolates in these analyses. A significant observation was that the haemolymph protein profile of nvWSSV‐infected shrimps showed three extra polypeptide bands at 41, 33 and 24 kDa that were not found in the haemolymph protein profile of vWSSV‐infected shrimps. The data obtained in this study suggest that the observed difference in the virulence of WSSV may not be due to any change in the virus, rather it could be due to the shrimp defence system producing certain factors that help it to accommodate the virus without causing any mortality.  相似文献   
998.
Disulphide Bonds in Wheat Gluten Proteins   总被引:2,自引:0,他引:2  
Disulphide bonds play a key role in determining the structure and properties of wheat gluten proteins. Comparison of the sequences of monomeric gliadins and polymeric glutenin subunits allows the identification of conserved and variant cysteine residues. Direct disulphide bond determination demonstrates that the conserved cysteine residues present in S-rich prolamins (α-type gliadins, γ-type gliadins and LMW subunits) form intra-chain disulphide bonds while additional cysteines residues present only in the LMW subunits form inter-chain bonds with cysteines in HMW subunits and other LMW subunits. Conserved and variant cysteine residues are also present in the HMW subunits but their patterns of disulphide bond formation are less well understood. Further information on the abilities of individual cysteine residues to form intra- and inter-chain disulphide bonds has also been obtained by heterologous expression of wild type and mutant proteins inE. coliand, in the case of the HMW subunits, by examination of the patterns of dimers recovered on partial reduction of glutenin or resulting from the expression of subunits in transgenic tobacco plants. Wheat gluten proteins are folded and assembled within the lumen of the endoplasmic reticulum of the developing endosperm cells, where disulphide bond formation and exchange may be catalysed by the enzyme protein disulphide isomerase. Similarly, disulphide bond reduction, for example to facilitate mobilisation during germination, may be catalysed by thioredoxinh. Understanding the mechanism and specificity of disulphide bond formation in gluten is crucial for the manipulation of its functional properties by genetic engineering or chemical modification.  相似文献   
999.
Crops resistant to insect attack offer an alternative strategy of pest control to a total reliance upon chemical pesticides. Transgenic plant technology can be a useful tool in producing resistant crops, by introducing novel resistance genes into a plant species. This technology is seen very much as forming an integral component of a crop management programme. Several different classes of plant proteins have been shown to be insecticidal towards a range of economically important insect pests from different orders; in some cases a role in the defence of specific plant species against phytophagous insects has been demonstrated. Genes encoding insecticidal proteins have been isolated from various plant species and transferred to crops by genetic engineering. Amongst these genes are those that encode inhibitors of proteases (serine and cysteine) and α-amylase, lectins, and enzymes such as chitinases and lipoxygenases. Examples of genetically engineered crops expressing insecticidal plant proteins from different plant species, with enhanced resistance to one or more insect pests from the orders Lepidoptera, Homoptera and Coleoptera are presented. The possibility of ‘pyramiding’ different resistance genes to improve the effectiveness of protection and durability is discussed and exemplified. The number of different crop species expressing such genes is very diverse and ever-increasing. The viability of this approach to crop protection is considered. © 1998 SCI.  相似文献   
1000.
Soil application of the systemic insecticide imidacloprid (Admire®, Bayer Crop Science) produced season-long control of citrus canker caused by Xanthomonas citri sbsp. citri. Imidacloprid is a neo-nicotinoid that breaks down in planta into 6-chloronicotinic acid, a compound closely related to the systemic acquired resistance (SAR) inducer isonicotinic acid. Potted Swingle citrumelo seedlings (Citrus paradisi × Poncirus trifoliata) were treated with imidacloprid and the SAR inducers, isonicotinic acid, and acibenzolar-s-methyl as soil drenches or with acibenzolar-s-methyl as a foliar spray 1week prior to inoculation of immature leaves with X. citri sbsp. citri. Seedlings were re-inoculated four times over a 24-week period. SAR induction was confirmed by expression of the PR-2 gene (β-1,3 glucanase). Soil drenches of imidacloprid, isonicotinic acid, and acibenzolar-s-methyl induced a high and persistent up-regulation of PR-2 gene expression and reduced the number of canker lesions for up to 24 weeks compared to 4 weeks for foliar acibenzolar-s-methyl. Soil applied inducers of SAR reduced canker lesions up to 70% compared with the untreated inoculated plants. Lesions on leaves were small, necrotic, and flat compared to pustular lesions on inoculated untreated plants. Populations of X. citri sbsp. citri per leaf were reduced 1–3 log units in soil-treated plants compared to inoculated untreated plants.  相似文献   
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