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1.
旨在探讨肉鸡胚胎在发育中后期肝脏蛋白水平的变化。本试验选取120枚重量为(65±0.2)g的罗氏308肉鸡种蛋,分为14胚龄(E14)和出壳1日龄(H1)两组,每组3个重复,每个重复20枚种蛋。孵化至E14胚龄和H1日龄时,采集肝脏组织样本,应用相对和绝对定量的等量异位标签(isobaric tags for relative and absolute quantitation,iTRAQ)结合生物信息学分析技术筛选核心差异蛋白。结果显示,在E14和H1日龄之间共筛选出10个核心差异蛋白,主要促进脂肪酸降解(上调ACOX1、ACSL1、ACSL5、CPT1A和ECI2)和糖异生(上调ALDH3A2、FBP1、FBP2、GPI和PGM2,下调LDHB和ALDH9A1)。试验结果提示,胚胎发育的主要能量供给途径是脂肪酸降解,而不是糖酵解。此外,糖异生增多,促进糖原储存以应对出壳以及营养环境变化。 相似文献
2.
In this paper, three approaches (Markov processes, discrete-event simulation, and differential equations) to modeling intramammary infections (IMI; focusing on the dynamic changes between uninfected, subclinical, and clinical udder-health states) are described. The objectives were to describe the various approaches to modeling intramammary infections, determine if simulations of the examples of the three approaches yield stable prevalences, and discuss the approaches' limitations. The literature review showed that there is no agreement on the proportion of animals that change health states. The approach of discrete-event simulation modeling included the most cow-level risk factors and udder-health states (hence, was judged to replicated best the dynamics of the infection process) and yielded stable prevalences for all udder-health states. However, there remain parts of the dynamics that need further research. These include the pathogen-specific probabilities and times of occurrence for: regression of clinical IMI to subclinical IMI, flare-up of subclinical IMI to clinical IMI, and incidence of subclinical IMI. Also, the assumption in all current approaches of homogenous mixing is violated because the primary contact structure for contagious pathogens during milking is either between cows through residual infectious milk in the milking machine or within a cow by vacuum fluctuations or teat-cup liner slips. Better contact structures should be incorporated so that the effects of control strategies can be better-estimated. Moreover, the three modeling approaches discussed assumed that all non-infected quarters are susceptible to infection—which might be denied by work in genetic resistance. 相似文献
3.
Sang-A GIM Dong-Ju PARK Ju-Bin KANG Fawad-Ali SHAH Phil-Ok KOH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):724
Glutamate induces neuronal damage by generating oxidative stress and neurotoxicities. The neurological damage caused by glutamate is more severe during brain development in newborns than in adults. Resveratrol is naturally present in a variety of fruits and medicinal plants and exerts a neuroprotective effect against brain damage. The goal of this study was to evaluate the neuroprotective effects of resveratrol and to identify changed proteins in response to resveratrol treatment during glutamate-induced neonatal cortical damage. Sprague-Dawley rat pups (7 days old) were randomly divided into vehicle, resveratrol, glutamate, and glutamate and resveratrol groups. The animals were intraperitoneally injected with glutamate (10 mg/kg) and/or resveratrol (20 mg/kg) and their brain tissue was collected 4 hr after drug administration. Glutamate exposure caused severe histopathological changes, while resveratrol attenuated this damage. We identified regulated proteins by resveratrol in glutamate-induced cortical damaged tissue using two-dimensional gel electrophoresis and mass spectrometry. Among identified proteins, we focused on eukaryotic initiation factor 4A2, γ-enolase, protein phosphatase 2A subunit B, and isocitrate dehydrogenase. These proteins decreased in the glutamate-treated group, whereas the combination treatment of glutamate and resveratrol attenuated these protein reductions. These proteins are anti-oxidant proteins and anti-apoptotic proteins. These results suggest that glutamate induces brain cortical damage in newborns; resveratrol exerts a neuroprotective effect by controlling expression of various proteins with anti-oxidant and anti-apoptotic functions. 相似文献
4.
旨在对绵羊胚胎骨骼肌蛋白质组学数据进行分析,为阐明绵羊胚胎骨骼肌生长发育机制奠定基础。前期试验应用串联质谱定量法(tandem mass tag,TMT)对成年中国美利奴绵羊妊娠第85(D85)、105(D105)和135天(D135)的胚胎背最长肌进行蛋白质定量,并对D85/D105、D105/D135和D85/D135 3个比较组进行分析。本试验在此基础上,利用KEGG和平行反应监测(parallel reaction monitoring,PRM)等数据分析方法对3个比较组绵羊胚胎骨骼肌上、下调差异丰度蛋白质进行分析和验证,并对候选蛋白质进行生物信息学分析。本研究对肌纤维成熟分化标志性蛋白肌球蛋白重链(myosin-2 isoform X2,MYH)进行PRM靶向定量验证,结果表明,其变化趋势与绵羊胚胎肌纤维成熟分化趋势相符。本研究对上调差异丰度蛋白和下调差异丰度蛋白的KEGG分析结果表明,D105/D85比较组中上调差异丰度蛋白质显著富集于胰岛素等信号通路,D135/D105和D135/D85比较组中下调差异丰度蛋白质显著富集于DNA复制和蛋白质消化吸收等信号通路。与肌肉发育相关的cAMP依赖性蛋白激酶A催化亚基α(PRKACA)和葡萄糖转运蛋白成员4(GLUT4)蛋白均显著富集于胰岛素信号通路中,生物信息学分析显示,这两个蛋白质的理论分子量分别为121.73和20.64 ku,分别有147、12个带正电荷的氨基酸残基和135、12个带负电荷的氨基酸残基;理论等电点分别为8.81和6.54;亲水性平均系数分别为-0.408和0.811;PRKACA蛋白无N端糖基化位点,有45个磷酸化位点;GLUT4蛋白有1个N端糖基化位点,25个磷酸化位点;PRKACA蛋白三级结构与CAMP-2依赖蛋白激酶a嵌合融合的晶体结构相似度为85%,GLUT4蛋白三级结构与人葡萄糖转运蛋白GLUT1的相似性为78%。本研究表明,PRM定量验证趋势与绵羊胚胎肌纤维成熟分化趋势相符,PRKACA和GLUT4蛋白具有丰富的磷酸化修饰位点,并参与胰岛素信号通路调控,是重要的候选蛋白。 相似文献
5.
为鉴定鸡羽髓上皮细胞感染马立克氏病病毒(MDV)前后差异表达的蛋白,本研究以MDV强毒GA株人工感染SPF鸡,并通过双向电泳技术进行分析.结果显示:在病毒感染后4 d、7 d、14 d和21 d显著差异表达的蛋白点分别有2个、8个、25个和9个;而通过质谱技术鉴定出29种蛋白质,其中包括能量代谢相关蛋白、增殖和凋亡相关蛋白、细胞骨架蛋白、信号传导蛋白、转录相关蛋白、免疫相关蛋白和其他功能蛋白质.本实验首次对鸡羽髓上皮细胞感染MDV后各时期蛋白表达水平的变化进行研究,鉴定了多种差异表达蛋白质,为进一步揭示MDV与宿主的相互关系、感染性病毒粒子的成熟和致病机制提供了依据. 相似文献
6.
A.M.A.M.Z. Siddiki Jonathan M. Wastling 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(3):203-210
Cryptosporidium (C.) spp. are important zoonotic parasites causing widespread diarrhoeal disease in man and animals. The recent release of the complete genome sequences for C. parvum and C. hominis has facilitated the comprehensive global proteome analysis of these opportunistic pathogens. The well-known approach for mass spectrometry (MS) based data analysis using the BLAST tool (MS BLAST) is a database search protocol for identifying unknown proteins by sequence similarity to homologous proteins using peptide sequences produced by mass spectrometry. We have used several complementary approaches to explore the global sporozoite proteome of C. parvum with available proteomic tools. To optimize the output of the MS data, a sequence similarity-based MS BLAST strategy was employed for bioinformatic analysis. Most significantly, almost all the constituents of glycolysis and several mitochondrion-related proteins were identified. In addition, many hypothetical Cryptosporidium proteins were validated by the identification of their constituent peptides. The MS BLAST approach was found to be useful during the study and could provide valuable information towards a complete understanding of the unique biology of Cryptosporidium. 相似文献
7.
8.
为寻找奶牛乳腺上皮细胞亚细胞结构中与泌乳相关的重要蛋白质、从蛋白质水平揭示乳蛋白合成的调控机制,应用双向凝胶电泳技术分离体外培养的蛋氨酸处理组与正常组奶牛乳腺上皮细胞蛋白质,利用Image Maser 2D软件对图谱进行对比分析,基质辅助激光解析电离飞行时间质谱(MALDI-TOF-MS)和数据库检索鉴定,并采用实时荧光定量PCR技术在mRNA水平上验证2-DE结果。质谱鉴定出8个表达上调的差异蛋白质,大多数差异蛋白质的功能涉及细胞骨架构成、能量代谢等过程。这些差异点的发现为研究奶牛泌乳机理提供了有益的线索。 相似文献
9.
分别从家蚕5龄幼虫和蛹期不同发育阶段提取雌、雄蚕血液总蛋白质,采用一维电泳-液相色谱-质谱(1DE-LC-MS)技术分析家蚕血液蛋白质的差异性表达及差异蛋白组分。在家蚕血液蛋白质含量与种类方面检测到与性别及发育相关的差异性表达,数据库检索结果共获得96个相匹配的候选蛋白质,剔除冗余部分后鉴定其中的27个蛋白质组分,分别属于13种蛋白质或其亚基。雌、雄蚕之间的差异组分主要出现在分子质量70~100 kD之间,其中芳基贮存蛋白、卵黄蛋白原、抗胰凝乳蛋白酶因子为雌特异性表达组分。30K蛋白家族是家蚕血液中高丰度表达的蛋白组分。这些差异蛋白质的鉴定与功能分析为研究家蚕性别发育调控机制提供了新的信息。 相似文献
10.