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1.
疱疹病毒是一类有囊膜的双链DNA病毒,基因组由长节段(L)和短节段(S)组成.UL31基因是基因组独特UL序列中的一个核心基因,具有典型的开放阅读框架,编码一种磷酸化蛋白.该蛋白与UL34蛋白相互作用,定位于细胞核边缘,与病毒核衣壳初期包膜形成有关,对病毒DNA的合成、包装和释放也有一定的作用.本文就UL31基因及编码蛋白的结构特点和基本功能等研究进展进行总结,以期为疱疹病毒UL31基因的深入研究提供指导.  相似文献   

2.
核纤层位于核膜内侧,主要由核纤层蛋白构成,对细胞核起重要的机械支持作用。编码核纤层蛋白的基因突变能导致人类肌肉、脂肪等组织病变,统称为核纤层病。为了研究柠檬苦素对牛前体脂肪细胞分化过程中核纤层蛋白基因表达的影响,试验利用qRT-PCR技术分析了编码核纤层蛋白的LMNA、LMNB1和LMNB2基因在牛前体脂肪细胞诱导分化过程中的表达变化,同时在细胞培养基中添加柠檬苦素,以分析柠檬苦素对细胞分化和核纤层蛋白编码基因表达的影响。结果表明:在培养基中添加柠檬苦素能够有效抑制牛前体脂肪细胞向成熟脂肪细胞的分化,试验组细胞中脂质沉积量极显著低于对照组(P0.01)。LMNA基因在牛前体脂肪细胞中具有较高的表达水平,添加柠檬苦素的试验组LMNA基因表达水平有降低的趋势。试验组LMNB1和LMNB2基因表达量在诱导分化的第0.5天极显著低于对照组(P0.01),在诱导分化的10~12 d试验组LMNB1基因表达量显著高于对照组(P0.05)。LMNA、LMNB1和LMNB2基因在牛前体脂肪细胞诱导分化过程中具有相似的表达变化趋势,均在诱导分化开始的0.5~1 d表达量升高。说明柠檬苦素在牛前体脂肪细胞早期分化时具有抑制核纤层蛋白基因表达的作用,而在分化后期则能够促进核纤层蛋白基因表达。  相似文献   

3.
疱疹病毒蛋白pUL34和pUL31在内核膜(INM)形成的复合物对于有效的核释出是必需的。伪狂犬病病毒(PRV)pUL34是含262个氨基酸(AA)的Ⅱ型膜蛋白。预测跨膜区(TM)位于245-261位,C端只有一个氨基酸,可能延伸到核周间隙。在缺失其他病毒蛋白时,其靶向核膜的固有定位基序,其结构与细胞INM蛋白,如Lap2β和Emer-in相似。为研究pUL34中与定位和功能有关的结构域,通过用细胞INM蛋白区域替换pUL34部分区域构建了嵌合蛋白。将C端18个氨基酸,包括TM替换为Lap2β和Emerin的TM和C端结构域,或核纤层蛋白B受体(LBR)的第一个TM,包括其后的9个氨基酸。所有由此产生的嵌合蛋白都弥补了PRV-ΔUL34的复制缺陷,表明TM的替代和C端结构域的扩展都不会干扰pUL34的功能。当C端50个氨基酸用相应的Lap2β序列取代(pUL34-LapCT50),其互补作用降低,但并没有阻断。然而,C端100个氨基酸(pUL34-LapCT100)替换后虽然仍能与pUL31结合,但会产生一个无功能的蛋白,说明这个区域在蛋白功能中起着重要的作用。N端100个氨基酸(pUL34-LapNT100)的替换对核膜定位没有影响,但能阻断pUL31的结合和功能。  相似文献   

4.
疱疹病毒蛋白pUL34和pUL31在内核膜(INM)形成的复合物对于有效的核释出是必需的。伪狂犬病病毒(PRV)pUL34是含262个氨基酸(AA)的Ⅱ型膜蛋白。预测跨膜区(TM)位于245-261位,C端只有一个氨基酸,可能延伸到核周间隙。在缺失其他病毒蛋白时,其靶向核膜的固有定位基序,其结构与细胞INM蛋白,如Lap2β和Emer-in相似。为研究pUL34中与定位和功能有关的结构域,通过用细胞INM蛋白区域替换pUL34部分区域构建了嵌合蛋白。将C端18个氨基酸,包括TM替换为Lap2β和Emerin的TM和C端结构域,或核纤层蛋白B受体(LBR)的第一个TM,包括其后的9个氨基酸。所有由此产生的嵌合蛋白都弥补了PRV-ΔUL34的复制缺陷,表明TM的替代和C端结构域的扩展都不会干扰pUL34的功能。当C端50个氨基酸用相应的Lap2β序列取代(pUL34-LapCT50),其互补作用降低,但并没有阻断。然而,C端100个氨基酸(pUL34-LapCT100)替换后虽然仍能与pUL31结合,但会产生一个无功能的蛋白,说明这个区域在蛋白质功能中起着重要的作用。N端100个氨基酸(pUL34-LapNT100)的替换对核膜定位没有影响,但能阻断pUL31的结合和功能。  相似文献   

5.
通过生物信息学分析、斑点杂交实验、克隆和测序证实了本实验室构建鸭瘟病毒(Duck plague virus,DPV)CHv株基因文库时新分离的基因(GenBank登录号EF643562)为DPV UL34基因,进一步运用有关分子生物学软件对该基因进行了分子特性分析。结果表明,该基因大小为831bp,编码276个氨基酸的多肽,含有疱疹病毒UL34类似蛋白家族保守区。系统进化树分析显示,其与α疱疹病毒亚科中马立克病毒属的GaHV-2,GaHV-3,MeHV-1,EHV-1和水痘病毒属的CeHV-9,HHV-3的亲缘关系最近,揭示DPV-CHv株应该被划为α疱疹病毒亚科中的单独一类。该编码蛋白在252~274位氨基酸有一个明显的跨膜区,C末端有一微体靶向序列(ARL),但无信号肽;含有4个酪蛋白激酶Ⅱ磷酸化位点,3个蛋白激酶C磷酸化位点,5个N-豆蔻酰化位点和1个N-糖基化位点;亚细胞定位主要位于细胞核;密码子偏爱性分析显示其偏爱的密码子第3位碱基多以A和T结尾,属于低表达基因;不同密码子使用频率与酵母、大肠杆菌和人的密码子使用频率比较表明,其与大肠杆菌和酵母较接近,与人差异较大。该分析结果揭示DPV UL34基因为一C端锚定的Ⅱ型膜蛋白基因,体外表达选择大肠杆菌和酵母表达系统较为合适,同时该结果也为进一步开展DPV UL34基因的生物学功能研究具有一定的参考作用。  相似文献   

6.
鸭瘟病毒UL47基因克隆及其分子特性分析   总被引:1,自引:0,他引:1  
通过测定本实验室构建的鸭瘟病毒(Duck plague virus,DPV)DNA基因文库中重组质粒的DNA序列,结合NCBI的ORF Finder和Blast工具分析得到了该病毒UL47基因的ORF。采用PCR扩增出了UL47基因并将其克隆到pMD18-T载体上,经PCR和酶切鉴定以及进一步的核酸斑点杂交试验证实该基因即为DPV UL47基因。利用生物信息学软件ProtScale、SignalP3.0、Scansite、TMpred、Prosite、DNAStar以及在线的EMBOSS等分析了UL47基因的分子特性。结果显示,该基因大小为2 367bp,编码788aa,而且与GenBank上多种α疱疹病毒同源蛋白的核酸和氨基酸序列具有较高的同源性。系统进化树分析表明,DPV UL47与禽类疱疹病毒(α-疱疹病毒)的进化关系最近。密码子偏爱性结果显示,DPV UL47编码相同氨基酸的不同密码子使用频率差异较大,UL47基因密码子使用模式更接近真核生物。研究结果为进一步开展DPV UL47基因功能研究奠定了基础。  相似文献   

7.
鸭瘟病毒部分基因的克隆与序列分析   总被引:5,自引:0,他引:5  
用BamH、EcoR、Hind、Pst、Sal 5种限制性内切酶消化鸭瘟病毒基因组DNA,回收2~6 kb片段连入pUC19载体,构建了鸭瘟病毒基因组部分文库。选取部分克隆进行序列测定,获得5个UL片段基因,分别为UL33、UL34、UL45、UL46和UL47。序列比较显示,它们与α-亚科疱疹病毒其他成员相应基因具有不同程度的同源性。这是国内外对鸭瘟病毒以上基因序列的首次报道。  相似文献   

8.
《中国兽医学报》2017,(8):1473-1478
UL48蛋白是MDV血清Ⅰ型(MDV-Ⅰ)复制所必需,其与MDV编码的另外一种具有去泛素化酶活性的被膜蛋白UL36以及其他被膜蛋白相互作用,为探究MDV编码的UL48与UL36互作在马立克氏病(MD)肿瘤发生机制中作用,本试验制备了致病型强毒MDV-Ⅰ编码的UL48的抗体。从MDV-Ⅰ基因组中克隆了UL48基因,并将测序正确的UL48基因分别亚克隆到pTYB1和pGEX-4T3原核表达载体,构建成pTYB1-UL48和pGEX4T3-UL48重组质粒。将两重组质粒分别转化到BL21(DE3)E.coli中,分别进行IPTG诱导表达,其中pTYB1-UL48表达的融合蛋白Intein-UL48应用Chitin-Sepharose进行亲和层析纯化,将纯化后的融合蛋白Intein-UL48作为免疫大白兔制备多克隆抗体,其中Intein标签有利于提高UL48蛋白的可溶性并提高抗体效价,pGEX4T3-UL48表达纯化的融合蛋白GST-UL48应用凝血酶进行切割得到UL48蛋白,以此为包被抗原,用于间接ELISA和Western blot抗体效价检测和特异性鉴定。结果显示该抗体效价为1:512 000,成功制备特异性的UL48抗体。  相似文献   

9.
利用靶基因步行 PCR 方法扩增得到鸭肠炎病毒(DEV Clone-03)5352 bp 基因片段,并进行克隆和测序.序列分析发现,该片段包含2个ORF.Blast 分析表明,这2个ORF分别与单纯疱疹病毒1型(HSV-1)UL51 和UL52 基因同源,命名为DEV Clone-03 UL51和UL52,分别编码252和1124个氨基酸.DEV Clone-03 UL51和UL52基因排列方式与HSV-1同源基因相一致,为"头对头"的转录方向,两个ORF间有236 bp 间隔序列.用DNAStar(Megalign)软件分别对这2个ORF和11株α-疱疹病毒参考毒株进行分析,发现DEV Clone-03 UL51 与HSV-1的氨基酸序列有相对较高同源性,DEV Clone-03 UL52与EHV-4 同源性相对较高.并且DEV Clone-03UL51基因在α-疱疹病毒中比较保守.与HSV-1 UL52 蛋白相似,DEV Clone-03 UL52蛋白C末端存在锌指结构.系统发育分析表明,DEV Clone-03与α疱疹病毒亚科成员的关系比较保守,与Mardivims属的成员具有较近的亲缘关系.  相似文献   

10.
以伪狂犬病病毒Ea株基因组DNA为模板,通过PCR扩增含UL31基因的1 000bp片段,扩增产物克隆于pMD18-T中,双脱氧末端终止法序列测定.通过OM1GA2.0软件包分析发现,Ea株UL31基因编码271个氨基酸,蛋白质分子量为30.38 kD,与Ka株UL31基因核苷酸与氨基酸序列同源性均在98%以上.将α-疱疹病毒亚科9个不同成员UL31同源基因编码的氨基酸序列进行多重比对分析,发现4个保守的功能性结构域.将该片段插入原核表达载体pGEX-KG中GST下游,构建的原核表达质粒pGEX-UL31在大肠杆菌BL32(DE3)中获得了高效表达,SDS-PAGE结果显示,表达的融合蛋白质分子量为56 kD.  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

14.
15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

17.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

18.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

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