谷子RNA干扰相关酶类基因家族的鉴定与分析

Dicers酶类、Argonautes蛋白以及RNA依赖的RNA聚合酶(RNA-dependent RNA polymerases,RDRs)是RNA干扰(RNA interference,RNAi)机制中重要的核心蛋白,但在谷子(Setaria italica)中尚无系统报道.为了研究谷子中与RNA干扰相关酶类基因的特征,本研究对谷子的RNA干扰相关酶类基因家族进行了蛋白质理化性质、亚细胞定位预测、蛋白质保守基序、基因保守结构域、基因家族成员间系统发育关系以及组织特异性表达谱分析.研究共发现24个与谷子RNA干扰相关酶类基因,包括7个DCL(Dicers),13个AGO(Argonautes),4个RDRs.系统进化树分析表明,这些家族被分为3个进化支.同一家族基因成员具有共同的保守结构域.虽然大多数基因可同时在不同发育时期的叶、茎和穗中表达,但其在各时期的穗和茎中的表达量最高.本研究为详细探讨这些基因在谷子生殖和生长发育中的表观遗传修饰作用提供了理论依据.     

RNA干扰的研究进展

RNA干扰(RNA interference,RNAi)现象是1998年在对秀丽线虫的研究中发现的.RNAi利用双链RNA(dsRNA)特异性地降解相应序列的mRNA.从而特异性地阻断相应基因的表达.本文介绍了RNA干扰现象的发现、分子机制、生物学意义及其技术的应用发展.     

RNA干扰及其在植物中的研究进展

RNA干扰(RNA interference,RNAi)是一种由双链RNA(double-stranded RNA,dsRNA)介导、能够特异沉默靶基因的转录后基因沉默现象,为植物基因功能的研究开辟了新途径.本研究主要综述了RNA干扰现象的发现、RNA干扰的过程及其特点、RNA干扰在植物中的诱导方法及载体构建、近年来R...     

基于CIRP基因有效干扰靶点的筛选

为了研究冷诱导RNA结合蛋白(CIRP)更深入的功能及意义,试验通过Lipo FiterTM将黑龙江八一农垦大学动物生理生化实验室之前已构建好的5组RNA干扰重组载体及空载体分别瞬时转染到大鼠肝细胞中,提取细胞RNA经反转录后进行荧光定量PCR试验,获得各组干扰载体对CIRP基因干扰后CIRP基因mRNA的相对表达量,确定效果最佳的干扰靶点。结果表明:在5组干扰试验组CIRP基因mRNA的表达量中,264组与空白对照组的表达量差异显著(P0.05),并且干扰效率达到70%以上;阴性对照组(空载体组)与空白对照组的表达量基本相同,差异不显著(P0.05)。说明试验成功筛选出有效干扰靶点。     

绵羊内皮生长因子siRNA载体构建及其在成纤维细胞中的表达

研究旨在构建绵羊血管内皮因子(VEGF)基因小干扰RNA(siRNA)载体并对其在成纤维细胞中的表达进行探索。实验构建了以VEGF基因片段为靶位点的3个siRNA质粒载体,即PGC-1、PGC-2、PGC-3,通过脂质体介导转染方法将干扰载体转入绵羊成纤维细胞中,利用ELISA测定3个干扰载体转染入成纤维细胞后细胞中VEGF的表达量。结果表明:各组转染后细胞中VEGF的表达量分别为47.78、24.45、8.36、13.99 pg/mL,转染载体PGC-2的成纤维细胞中VEGF表达量最少。上述结果说明,在绵羊成纤维细胞中可发生RNA干扰现象,且干扰载体PGC-2的干扰效率最高,RNA干扰技术有效改变了VEGF的基因表达。     

谷子RNA干扰相关酶类基因家族的鉴定与分析

Dicers酶类、Argonautes蛋白以及RNA依赖的RNA聚合酶(RNA-dependent RNA polymerases, RDRs)是RNA干扰(RNA interference, RNAi)机制中重要的核心蛋白,但在谷子(Setaria italica)中尚无系统报道。为了研究谷子中与RNA干扰相关酶类基因的特征,本研究对谷子的RNA干扰相关酶类基因家族进行了蛋白质理化性质、亚细胞定位预测、蛋白质保守基序、基因保守结构域、基因家族成员间系统发育关系以及组织特异性表达谱分析。研究共发现24个与谷子RNA干扰相关酶类基因,包括7个DCL (Dicers),13个AGO (Argonautes),4个RDRs。系统进化树分析表明,这些家族被分为3个进化支。同一家族基因成员具有共同的保守结构域。虽然大多数基因可同时在不同发育时期的叶、茎和穗中表达,但其在各时期的穗和茎中的表达量最高。本研究为详细探讨这些基因在谷子生殖和生长发育中的表观遗传修饰作用提供了理论依据。     

捻转血矛线虫感染性三期幼虫gst基因的筛选及抗干燥功能分析

为研究干燥作用对捻转血矛线虫L3期幼虫mRNA表达的影响,筛选并分析干燥相关表达基因,本试验利用mRNA差异显示技术得到了捻转血矛线虫干燥相关基因,通过相对荧光定量PCR验证所获基因的表达情况,并在秀丽隐杆线虫中通过RNA干扰抑制相关同源基因的表达检测干燥后复苏虫体生存率以研究基因抗干燥功能。结果显示,差异表达序列GH-U02A与已知捻转血矛线虫谷胱甘肽-S-转移酶(GST)氨基酸同源性为94%。对秀丽隐杆线虫Ce-gst-7基因进行RNA干扰后,虫体在干燥后的生存率降低,证明gst基因在线虫中有抗干燥功能。     

PTEN基因干扰对牛脂肪细胞凋亡的影响

实验旨在研究RNA干扰PTEN基因对牛脂肪细胞中p-Akt蛋白及凋亡蛋白Caspase-3表达的影响。将人工合成的靶向PTEN基因的3条干扰质粒Si-952组、Si-1331组、Si-1435组及阴性对照组(只加转染阴性对照质粒)和空白组(只加PBS缓冲液),在脂质体介导下转染牛脂肪细胞,用RT-qPCR方法检测并筛选干扰效率最高的1条Si RNA。Western blot法检测PTEN基因沉默后对p-Akt和Caspase-3表达的影响。结果表明:PTEN-Si-1331组干扰效率最高,转染48 h后抑制率可达85%;牛脂肪细胞转染Si-1331组Caspase-3蛋白表达水平极显著低于阴性对照组和空白组(P0.01),而p-Akt蛋白表达水平显著高于阴性对照组和空白组(P0.01)。上述结果表明,干扰PTEN基因能显著抑制Caspase-3的表达,提高p-Akt的表达,揭示低表达PTEN通过调控Akt信号通路抑制牛脂肪细胞凋亡。     

寄生线虫RNA干扰研究进展

基因的RNA干扰（RNA interference,RNAi）技术是一个功能强大的基因组学研究工具。机体内存在特定的双链RNA（dsRNA）对基因的表达有干扰作用,可以引起基因沉默现象。通过外源dsRNA对寄生线虫进行RNA干扰研究,有助于了解不同发育期的特征现象和特定基因的生物学功能。此外,寄生线虫的RNA干扰研究对RNA干扰技术本身的发展也有较大促进作用。作者总结了近几年来RNA干扰技术在寄生线虫方面的最新研究进展,以期为相关研究工作提供参考。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Mechanism of Action of Probiotic Function of Lactobacilli

乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.