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281.
In male three-spined sticklebacks, Gasterosteus aculeatus, the kidney hypertrophies during the breeding season and produces a glue which is used in nest-building. This hypertrophy is androgen dependent with 11-ketotestosterone (11 KT) being most effective. The aim of the present study was to characterize the protein composition of this glue. Threads of glue were collected from stickleback nests and glue material was sampled from the content of urinary bladders of male sticklebacks in breeding condition. The samples were investigated using sodium dodecyl sulphate- polyacrylamide gel electrophoresis (SDS-PAGE). One major glycoprotein dominated in both the nest-threads and urinary bladder samples. The identified glycoprotein had a molecular mass of approximately 203 kDa. After deglycosylation the molecular mass was approximately 200 kDa. The amino acid composition of the protein from urinary bladder content was almost identical to the amino acid composition of the protein from the nest-threads. The protein had a relatively high content of cysteine (7.6–8.0%). The glycoprotein was named spiggin. Spiggin was absent in the urinary bladder of untreated castrated fish, but spiggin was present in sham- operated fish and in castrated fish treated with 11 KT. These results demonstrate that spiggin is induced by 11 KT. Spiggin is so far the only protein known to be induced by 11KT and based on the present findings we suggest that spiggin represents a novel structural protein.  相似文献   
282.
鸡传染性支气管炎病毒W株膜蛋白基因的分子特征   总被引:1,自引:0,他引:1  
【目的】研究鸡传染性支气管炎病毒(IBV)W株膜蛋白基因的分子特征。【方法】根据GenBank中已发表的鸡传染性支气管炎病毒M基因序列,设计并合成1对特异性引物,利用RT-PCR技术成功扩增了IBV河南地方分离毒株W株M基因全长片段,然后进行克隆、测序,并与GenBank中发表的11株国内外参考毒株进行比较分析。【结果】获得的W株M基因全长为681 bp,编码M蛋白226个氨基酸残基,其N端的前60 nt为前导序列,近N端含有2个潜在的N-糖基化位点;3个跨膜区域分别位于21~37,45~68,74~94 aa处,在171~176,183~193 aa处有2个潜在的抗原位点,且M蛋白上有9个高度保守的半胱氨酸;与参考毒株相比,IBV-W株M基因的核苷酸同源性为88.2%~92.7%,推导的氨基酸同源性为91.1%~95.6%;M蛋白的突变主要发生在前16位氨基酸,其中第2位缺失1个氨基酸,第3~6位连续插入4个氨基酸,第8~9位缺失2个氨基酸,第14~16位的3个氨基酸发生连续突变,其他位点的氨基酸变异为点突变,M蛋白核苷酸序列的变异主要表现为静默突变,亲水区较疏水区更易变易;在系统发生进化树中,W株与BJ株处于同一个小的分支上,亲缘关系较近,而与其他参考株的亲缘关系较远。【结论】推测W株可能是一个新的变异株。  相似文献   
283.
以菲律宾蛤仔肉为研究对象,水提醇沉,Sevag法除蛋白,DEAE—SepharoseFF阴离子交换层析柱分离纯化,SephadexG-25凝胶柱除盐,得到1种白色组分,红外显示该组分具有糖蛋白的一般吸收特征。将该糖蛋白作用于前列腺癌细胞DU-145进行体外药物敏感性实验,结果显示,0.1moFL氯化钠溶液的洗脱峰组分对DU-145细胞具有明显增殖抑制作用。最适作用浓度约为25mg/mL,表明菲律宾蛤仔具有潜在的抗肿瘤作用。  相似文献   
284.
Cloning and Sequence of Glycoprotein H Gene of Duck Plague Virus   总被引:9,自引:0,他引:9  
The glycoprotein H (gH) gene homologue of duck plague virus (DPV) was cloned by degenerate polymerase chain reaction (PCR) and sequenced. It was located immediately downstream from the thymidine kinase gene (TK). In addition, the 3'-end of the gene homologue to herpesvirus UL21 was located downstream from the gH gene. DPV gH gene open reading frame (ORF) was 2 505 bp in length and its primary translation product was a polypeptide of 834 amino acids long. It possessed several characteristics of membrane glycoproteins, including an N-terminal hydrophobic signal sequence, an external domain containing eight putative N-linked glycosylation sites, a C-terminal transmembrane domain, and a charged cytoplasmic tail. Comparison with other herpesvirus revealed identities of 20.2, 25.1, 23.0, 23.0, 26.5 and 26.0% with the gH counterparts of the human herpesvirus virus 1 (HSV1), equine herpesvirus 4 (EHV4), bovine herpesvirus 1 (BHV1), pseudorabies virus (PRV), gallid herpesvirus 2 (GHV2) and gallid herpesvirus 3 (GHV3), respectively.  相似文献   
285.
Herpes simplex virus type 1 (HSV-1) is one of the most prevalent pathogens worldwide requiring the search for new candidates for the creation of antiherpetic drugs. The ability of sea urchin spinochromes—echinochrome A (EchA) and its aminated analogues, echinamines A (EamA) and B (EamB)—to inhibit different stages of HSV-1 infection in Vero cells and to reduce the virus-induced production of reactive oxygen species (ROS) was studied. We found that spinochromes exhibited maximum antiviral activity when HSV-1 was pretreated with these compounds, which indicated the direct effect of spinochromes on HSV-1 particles. EamB and EamA both showed the highest virucidal activity by inhibiting the HSV-1 plaque formation, with a selectivity index (SI) of 80.6 and 50.3, respectively, and a reduction in HSV-1 attachment to cells (SI of 8.5 and 5.8, respectively). EamA and EamB considerably suppressed the early induction of ROS due to the virus infection. The ability of the tested compounds to directly bind to the surface glycoprotein, gD, of HSV-1 was established in silico. The dock score of EchA, EamA, and EamB was −4.75, −5.09, and −5.19 kcal/mol, respectively, which correlated with the SI of the virucidal action of these compounds and explained their ability to suppress the attachment and penetration of the virus into the cells.  相似文献   
286.
本试验通过PCR方法以猪伪狂犬病病毒SD株的基因组DNA为模板扩增得到了含gD主要抗原表位编码区的片段,将该PCR产物克隆到pGEM-T载体上,酶切后插入原核表达载体pET-32a的T7启动子下游。构建的重组质粒pET-gD经IPTG诱导,在大肠杆菌BL21(DE3)中获得了高效表达。SDS-PAGE结果显示,表达产物分子质量约为45.2 ku,主要以包涵体形式存在。表达产物用His亲和层析柱纯化。Western blotting结果显示,该纯化蛋白能与猪伪狂犬病病毒抗体阳性血清发生特异性反应,表明该重组蛋白具有良好的抗原反应性,可以作为猪血清伪狂犬病病毒抗体诊断用抗原。  相似文献   
287.
妊娠相关糖蛋白(pregnancy-associated glycoprotein,PAG)是由胎盘组织产生并释放到母体外周血液中的大分子蛋白,在妊娠过程中发挥着重要作用.目前,母畜妊娠早期诊断的研究多集中在对奶牛伤害小、准确性高、特异性强的间接检测方法上,如检测血液或乳汁中孕酮等激素,而近年来发展起来的对血液中PAG的检测就是一种主流的方法.作者现就PAG的功能、生化特性、母畜怀孕期间PAG的浓度变化及其在反刍动物早期妊娠诊断中的应用情况进行综述.  相似文献   
288.
猪瘟病毒囊膜结构(糖)蛋白Erns和E2的生物学特性研究   总被引:7,自引:0,他引:7  
猪瘟病毒(CSFV)、牛病毒性腹泻病毒(BVDV)、边界病病毒(BDV)和长颈鹿瘟病毒(Giraffe pestvirus)为黄病毒科瘟病毒属成员,其病毒结构、抗原性和遗传特性密切相关.CSFV囊膜结构(糖)蛋白E2(gp55)是诱导机体产生中和抗体及激发保护性免疫应答的主要抗原蛋白.囊膜结构(糖)蛋白Erns/E0(gp48)具有BNA酶活性,在病毒增殖及中和病毒感染中发挥重要作用,是诱导机体产生保护性免疫应答的第二抗原蛋白.E2和Ens与细胞表面受体的相互作用介导CSFV对细胞的感染过程.本文综述CSFV囊膜结构(糖)蛋白Erns和E2的生物学特性研究进展.  相似文献   
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