黑腹果蝇先天免疫研究进展

先天免疫是昆虫适应复杂环境的关键,也是新型害虫防治的重要研究方向。昆虫通过模式识别受体识别环境中不同的病原物,激活先天免疫系统以清除病原物。昆虫的先天免疫系统主要包括体液免疫与细胞免疫,体液免疫包括免疫信号通路诱导产生抗菌肽、活性氧以及黑化作用等,细胞免疫包括血细胞的吞噬、包囊和凝结。本文将重点总结黑腹果蝇Drosophila melanogaster在模式识别受体、免疫信号通路和细胞免疫相关方面的研究进展,为进一步研究其他经济昆虫与农业害虫的免疫机制,提高生产经济效益提供参考。     

谷氨酸钠摄入引起的果蝇肠道菌群多样性变化研究

谷氨酸钠(MSG),也称味精,是谷氨酸的钠盐,也是最丰富的天然存在的非必需氨基酸之一.MSG常作为一种增味剂被添加到食物中,但也有报道可引起哮喘、头痛甚至脑损伤.本文以黑腹果蝇作为材料,利用16S rDNA扩增子测序分析其肠道菌群对高MSG摄人的响应.结果发现饲喂MSG组果蝇相比对照组,其肠道的厚壁杆菌门 Firmic...     

白癜风患者病变表皮与正常表皮的比较蛋白质组学研究（英文）

目的 本文通过开展白癜风患者病变表皮与正常表皮的比较蛋白质组学研究，发现和鉴定白癜风患者病变表皮与正常表皮之间的差异表达蛋白，以探讨白癜风患者表皮发生病变的分子机制。方法 首先，建立和优化了表皮样品中蛋白质的最佳酶切条件。其次，采用基于串联质谱标签（TMT）标记的定量蛋白质组学技术策略开展了稳定期白癜风患者病变表皮与正常表皮的比较蛋白质组学研究，并筛选了差异表达蛋白。最后通过生物信息学分析工具及数据库（GO、KEGG、STRING、GSEA）对差异蛋白进行功能富集分析。结果 优化所得到的最佳酶解条件是由Lys-C （酶∶底物，1∶100）和胰酶（酶∶底物，1∶50）组合而成的顺序酶切。比较蛋白质组学研究共鉴定4 496个蛋白质，其中181个蛋白质为白癜风患者病变表皮中的差异表达蛋白。生物信息学分析表明差异表达蛋白主要与代谢、免疫、氧化还原和细胞黏附相关。其中119个上调蛋白主要参与角质化、转录、氧化应激及蛋白酶解等过程。62个下调蛋白主要参与细胞内物质运输、谷胱甘肽代谢和肌动蛋白细丝封端等过程。结论 比较蛋白质组学研究揭示了白癜风患者病变表皮与正常表皮之间主要存在角质化、免疫、脂质代谢...     

人类小腿肌肉对运动训练生理响应的电学特性研究

目的 运动训练已被证明能够改善许多慢性肌肉功能疾病,被用于治疗衰老型肌萎缩。本文采用电阻抗成像(electrical impedance tomography,EIT)研究人类小腿肌肉对运动训练生理响应的电学特性,旨在使用EIT方法可视化运动训练对人类小腿响应肌肉隔室内肌肉纤维体积增加的效果。方法 实验对象被要求在连续5个实验日进行左、右腿单侧提踵训练,应用EIT检测每日运动训练前和运动训练后小腿肌肉的电导率分布。为了定量分析运动训练对响应肌肉隔室的作用,使用配对样本t检验分析EIT重建图像的空间平均电导率<σ>。结果 运动训练后,由小腿腓肠肌组成的M₁肌肉隔室空间平均电导率<σ>_M1显著增加。此外,连续5个实验日的EIT测量结果显示,运动训练前的空间平均电导率<σ^pre>_M1呈上升趋势。所有实验对象在实验日1早晨进行实验前的腿部瘦体重与<σ>_M1呈线性关系,即<σ>_M1随腿部瘦体重增加而增加;运...     

偏头痛患者体感刺激下脑电信号的功能连接（英文）

目的 偏头痛是一种复杂的脑功能障碍性疾病,全球范围内患病率为14.4%。功能连接测量两个神经信号之间的统计学相互依赖性,不同的功能连接反映了大脑区域协同工作的不同模式。因此,研究不同脑区的功能连接对于理解偏头痛的病理生理机制具有十分重要的意义。以往基于脑电图对偏头痛患者脑功能连接的分析主要集中在视觉和疼痛刺激。本文尝试研究偏头痛患者在发作间期对体感刺激的皮质反应,以进一步了解偏头痛的神经功能障碍,为偏头痛的预防和治疗提供线索。方法 招募23例无先兆偏头痛患者,10例有先兆偏头痛患者,28名健康对照者。所有受试者均进行详细的基本资料和病史采集,完善量表评估,在正中神经体感刺激下进行脑电图记录。计算68个脑区的相干性作为功能连接,并评估功能连接与临床参数的相关性。结果 在正中神经体感刺激下,无先兆偏头痛和有先兆偏头痛患者的脑电功能连接与对照组相比存在差异,异常的脑电功能连接主要位于感觉辨别、疼痛调节、情绪认知和视觉处理等区域。无先兆偏头痛和有先兆偏头痛患者的大脑皮层对体感刺激可能具有相同的反应方式。偏头痛患者的功能连接异常与临床特征之间存在相关性,可以部分反映偏头痛的严重程度。结论 本研究...     

定量分析调控人类免疫缺陷病毒潜伏与激活的动力学机制

目的 治疗艾滋病最大的障碍在于无法根除人类免疫缺陷病毒（HIV）潜伏于人体细胞所形成的病毒存储库。构建描述病毒存储库建立分子机制的动力学模型需考虑生物体内的噪声环境和多重影响因素,本文通过一种全新的动力学结构分解方法将随机微分方程的确定性部分与随机性噪声分开,从而在仅需分析常微分方程不动点的情况下即可判断不同药物靶点的作用效果。方法 使用连续的随机微分方程构建了HIV转录过程的动力学模型,简化了描述系统所需方程的维度,增大了模型的可探索空间,在此基础上,通过计算得到的势能函数和概率分布函数直观表示病毒潜伏与激活的不同表达状态以及它们之间的关系。结果 定量分析了不同动力学参数对系统稳态和势函数的影响程度,分别得到了系统处于双稳态和单稳态时的参数范围,并将不同因素对动力系统分岔的影响程度与生物学实验结果对比,验证了本工作的理论基础。结论 本文突破了以往离散、随机的方法,可以通过常微分方程定量分析HIV转录调控的动力学机制,有利于推广到处理高维情况,进一步研究艾滋病在生物体内的发生发展,从而指导设计实验寻找临床上的治疗方案。     

Notch信号途径中的Su(H)和E(spl)基因对果蝇天然免疫的影响

天然免疫系统是多细胞生物抵抗各种入侵微生物的第一道防线.Notch途径介导相邻细胞之间的相互作用,调节细胞、组织、器官的分化和发育.为了进一步探索Notch信号途径在果蝇天然免疫中的功能,利用Notch途径下游基因Su(H)和E(spl)的低表达突变体果蝇,通过体外注射病原体分析了生存率、血细胞的噬菌功能和抗菌肽的表达量以及突变体的血细胞数量.结果表明,革兰氏阴性细菌和真菌感染后果蝇E(spl)突变体的生存率、噬菌能力及抗菌肽的表达量明显降低,而且幼虫期血细胞出现异常增殖;Su(H)突变体只对真菌表现出敏感性,抗菌肽的表达量降低,但是对真菌的噬菌能力正常.此结果表明,Notch途径不仅影响个体的生长发育,而且在果蝇天然免疫中也起重要的调节作用.     

酶类药物现状、问题及展望

随着生物制药的迅速发展,许多酶类药物应运而生,在治疗代谢疾病、心血管疾病、癌症等诸多疾病上发挥着越来越重要的作用。但是酶类药物也存在一些不足,如潜在的免疫原性、较短的体内半衰期,以及较差的组织靶向性,影响了酶类药物的疗效和应用。为克服这些缺点,人们已开发出多种技术,如通过糖基化、聚乙二醇修饰等分子工程技术提升酶蛋白药效,另一方面酶基因疗法也已成功用于多种酶缺陷疾病的治疗。基于酶类药物的迅速发展和广泛的应用前景,本文对酶类药物的现状进行较详细的阐述,并对酶类药物的优势、所存在的问题及未来发展趋势进行分析和评述。     

胡麻亚麻酸亚油酸相关KASP标记的开发

胡麻是北方地区特有的、富含不饱和脂肪酸的油料作物。培育高亚麻酸品种、高亚油酸品种是胡麻品质育种的主要目标。分子标记辅助选择能提高胡麻育种效率,缩短育种年限。本研究进行了胡麻资源材料自然群体多年多点脂肪酸检测数据的统计分析和基因分型、群体构建、亚麻酸、亚油酸相关SNP位点的KASP基因分型及其验证等研究,取得了以下几个方面的结果：（1）检测246份胡麻种质资源材料多年多点5种脂肪酸成分,并对其进行了统计分析。相关性分析结果显示,亚麻酸与其他成分之间呈极显著负相关,尤其是亚麻酸和亚油酸之间负相关性最高;（2）对5种脂肪酸表型数据进行统计分析,确定了亚麻酸、亚油酸相关SNP标记分型群体：包括49份高亚麻酸（≥54%）材料、36份低亚油酸（≤13.5%）材料,及8号（CH-89）和254号（CI637PI91037）高亚油酸低亚麻酸材料;（3）验证并确定了7个SNP位点：g6-6229142、g10-19305239、g9-18961021与亚麻酸显著关联;g6-19208888、g9-14900088、g15-22369840和g2-7680441与亚油酸显著关联;（4）对确定的7个SNP位...     

沙子岭猪肝脏细菌和脂质图谱研究

近年来,有研究提示动物内脏组织含有少量细菌,它们参与了脏器组织生理代谢反应.本实验以成年沙子岭猪和大白猪为实验模型,比较了二者肝脏细菌组成以及脂质代谢图谱,并通过Pearson关联分析解析二者之间的互作关系. 16S rDNA测序提示,沙子岭猪和大白猪肝脏均含有一定丰度的细菌,且二者细菌组成存在明显差异.在门水平上,沙子岭猪肝脏变形菌门(Proteobacteria)和衣原体(Chlamydiae)丰度显著高于大白猪;在属水平, 14种细菌在沙子岭猪和大白猪肝脏存在显著差异.沙子岭猪和大白猪肝脏脂质组学筛选出37个差异代谢脂质,其中6个脂质在脂肪型沙子岭猪肝脏显著富集, 31个脂质在瘦肉型大白猪肝脏富集; Pearson关联分析证实,肝脏细菌可能参与脂质代谢,其中13种差异细菌与35种差异代谢脂质显著相关.综上所述,不同代谢类型动物模型肝脏细菌组成存在差异,且可能对脂质代谢具有重要的作用,并影响动物代谢表征.     

Paucimannose N-glycans in Caenorhabditis elegans and Drosophila melanogaster

There is a rich diversity of paucimannose N-glycans in worms and flies, and these may play a role in the survival of these organisms. Although paucimannose N-glycans are not expressed in vertebrates, complex N-glycans may take over some of the functions of paucimannose N-glycans. Identification of the target proteins of β-1,2-N-acetylglucosaminyltransferase I (GnTI) in worms and flies and elucidation of their functions may thus lead to a better understanding of the role of GnTI-dependent glycoproteins in the survival/longevity of both invertebrates and vertebrates.     

The sibling species Drosophila melanogaster and Drosophila simulans differ in the expression profile of glutathione S-transferases

Two major forms of glutathione S-transferase are known in Drosophila melanogaster: GST D and GST 2. In the present paper we report the existence of a third major form of glutathione S-transferase in Drosophila simulans. Induction with phenobarbital revealed a different regulation of GST between these species. Despite the fact that these two species are closely related, there was a difference in the expression profile of the enzyme implicated in the detoxification system, suggesting variations in capacity to suit their environment.     

The effect of environmental temperature on olfactory perception in Drosophila melanogaster

Olfaction provides chemical information to an animal about its environment. When environmental conditions change, individuals should be able to adequately maintain function. Temperature may influence olfaction in a double manner, as it modifies the concentrations of gaseous compounds and affects biological processes. Here, we address acclimatization to environmental temperature in the olfactory system of Drosophila melanogaster using heat and cold treatments. Because the consequences of temperature shifts persist for some time after the treatment's end, comparison of olfactory behaviors at the same temperature in treated and untreated flies allows us to infer the biological effects of temperature in olfaction.At intermediate odorant concentrations heat always generates a reduction of olfactory sensitivity, as they would be expected to compensate for the increase of volatiles in the air. Cold produces the opposite effect. These changes are observed in both sexes and in natural populations as well as in standard laboratory stocks.Short applications suffice to cause detectable olfactory perception changes, but even prolonged temperature treatments have only a transitory effect. Together, these results suggest that olfaction in Drosophila underlies acclimatization to environmental temperature. However, sensitivity changes are not immediate and may cause imperfect adjustment of olfactory function for short time periods.     

模拟微重力效应对果蝇运动及睡眠的影响

本研究旨在探讨利用模拟微重力效应研究微重力对果蝇运动及睡眠影响的可行性.通过研制能够在模拟微重力环境下实时监测果蝇行为的随机定位仪,监测短时间(3 d)模拟微重力处理过程中,及长时间(10 d、20 d、30 d)处理后雄蝇运动和睡眠的变化;选取受影响较显著的短时间处理组,研究模拟微重力效应对生物钟核心基因(period (per)、timeless(tim)、clock (clk)、cycle (cyc)、cryptochrome (cry))、神经递质多巴胺(dopamine,DA)和5-羟色胺(5-hydroxytryptamine,5-HT)关键合成酶(多巴脱羧酶、酪氨酸羟化酶、色氨酸羟化酶)的编码基因ddc、pale和trh表达水平及DA和5-HT含量的影响.结果显示:短时间暴露下,雄蝇夜晚的运动量增加、单位时间运动次数增加、睡眠时间和次数减少、生物钟基因tim、clk、cyc、cry及神经递质合成相关编码基因ddc、pale和trh的表达水平均显著上升;长时间处理后对雄蝇运动和睡眠的影响较小.本研究认为利用模拟微重力效应研究微重力对果蝇运动及睡眠的影响是可行的,相关研究结果对航天医学研究具有借鉴意义.     

Constitutive heterochromatin in early embryogenesis of Drosophila melanogaster

Summary The formation of constitutive heterochromatin was studied during the embryonic development of Drosophila melanogaster, using the C-banding technique. During embryonic cleavage, C-banded material is not seen in mitotic chromosomes; the differentiation between euchromatin and heterochromatin only occurs at blastoderm. This event correlates with the establishment of position-effect variegation.     

Carnitine suppression of position-effect variegation in Drosophila melanogaster

Carnitine is a well-known naturally occurring compound, very similar to butyrate, with an essential role in intermediary metabolism mainly at the mitochondrial level. Since butyrate inhibits the enzyme histone deacetylase and is capable of suppressing position-effect variegation in Drosophila melanogaster, we tested a further possible function of carnitine in the nucleus, using an assay for the suppression of position-effect variegation. We tested three physiological forms of carnitine (l-carnitine, l-propionylcarnitine, l-acetylcarnitine) for the ability to suppress two different chromosomal rearrangements, inducing variegation of the white ⁺ and brown ⁺ genes. The results show that the carnitine derivatives are capable of suppressing the position-effect variegation, albeit with different efficiencies. The carnitine derivatives interact lethally with Su-var(2)1 ⁰¹, a mutation that induces hyperacetylation of histones, whilst hyperacetylated histories accumulated in both the nuclei of HeLa cells and Drosophila polytene chromosomes treated with the same compounds. These results strongly suggest that the carnitine derivatives suppress position-effect variegation by a mechanism similar to that of butyrate. It is suggested that carnitines may have a functional role in the nucleus, probably at the chromatin level.     

Synthesis of Drosophila melanogaster acetylcholinesterase gene using yeast preferred codons and its expression in Pichia pastoris

To improve the expression level of recombinant Drosophila melanogaster AChE (R-DmAChE) in Pichia pastoris, the cDNA of DmAChE was first optimized and synthesized based on the preferred codon usage of P. pastoris. The synthesized AChE cDNA without glycosylphosphatidylinositol (GPI) signal peptide sequence was then ligated to the P. pastoris expression vector, generating the plasmid pPIC9K/DmAChE. The linearized plasmid was homologously integrated into the genome of P. pastoris GS115 via electrotransformation. Finally seven transformants with high expression level of R-DmAChE activity were obtained. The highest production of R-DmAChE in shake-flask culture after 5-day induction by methanol was 718.50 units/mL, which was about three times higher than our previous expression level of native DmAChE gene in P. pastoris. Thus, these new strains with the ability to secret R-DmAChE in the medium could be used for production of R-DmAChE to decrease the cost of the enzyme expense for rapid detection of organophosphate and carbamate insecticide residues.     

Aurora, a non-mobile retrotransposon in Drosophila melanogaster heterochromatin

A novel retrotransposon, aurora, containing 324 by long terminal repeats (LTRs) was detected in Drosophila melanogaster as a 5 kb insertion in the heterochromatic Stellate gene. This insertion causes a 5 bp duplication of the integration site. Southern analysis and in situ hybridization data show that all detectable copies of aurora are immobilized in the D. melanogaster heterochromatin. However, mobile copies of aurora were revealed in the cuchromatin of D. simulans. The element was also found in various species of the melanogaster subgroup and in the D. virilis genome.The nucleotide sequence data reported in this paper will appear in the EMBL, GenBank and DDBJ Nucleotide Sequence Databases under the accession numbers X70361 and X70362