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A large number of plant microRNAs (miRNAs) are now documented in the miRBase, among which only 30 are for Solanum lycopersicum (tomato). Clearly, there is a far-reaching need to identify and profile the expression of miRNAs in this important crop under various physiological and pathological conditions. In this study, we used an in situ synthesized custom microarray of plant miRNAs to examine the expression and temporal presence of miRNAs in the leaves of tomato plants infected with Cucumber mosaic virus (CMV). Following computational sequence homology search and hairpin structure prediction, we identified three novel tomato miRNA precursor genes. Our results also show that, in accordance with the phenotype of the developing leaves, the tomato miRNAs are differentially expressed at different stages of plant development and that CMV infection can induce or suppress the expression of miRNAs as well as up-regulate some star miRNAs (miRNA*s) which are normally present at much lower levels. The results indicate that developmental anomalies elicited by virus infection may be caused by more complex biological processes.  相似文献   

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目的:寻找来源于Alport综合征患者与正常对照者的多能干细胞差异性表达的microR NA,并对差异性表达的microR NA靶基因进行预测。创新点:本研究不同于一般的试验标本,试验标本是来源于尿肾脏管细胞诱导而成的多能干细胞。基于Alport综合征是遗传疾病,我们对一遗传家系进行了系统的分析。寻找特异性的差异性表达microR NA及其靶基因,从基因水平对Alport综合征进行研究。方法:在前期工作中,成功地从实验者与对照者的尿肾脏管细胞诱导成多能干细胞。运用高通量测序技术分析并发现实验者与对照者之间差异性表达的microR NA。对差异性表达的microR NA靶基因进行预测,并进行靶基因聚集分析,研究靶基因主要参与的生物学过程。同时进行靶基因信号传导通路的分析,研究靶基因主要参与的细胞信号传导通路。结论:在实验组与对照组之间,发现了30个具有显著差异性表达的microR NAs,包括19个上调表达与11个下调表达。差异性表达的microR NA的靶基因主要聚集在细胞膜和细胞代谢过程;靶基因主要参与嘌呤代谢通路与丝裂原活化蛋白激酶(MAPK)通路。  相似文献   

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miRNA(microRNA)是一类长约22个核苷酸的小分子非编码RNA。近年来,科学家发现miRNA与基因表达调控密切相关,miRNA可通过与靶mRNA特异性的碱基配对,引起靶mRNA的降解,抑制其翻译,或以其它形式的调节机制抑制靶基因的表达。本文概述了miRNA特点、生物合成过程、功能以及作用机制。  相似文献   

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MicroRNAs (miRNAs or miRs) are endogenous non-coding RNAs that negatively regulate gene expression by binding to the 3′ non-coding regions of target mRNAs, resulting in their cleavage or blocking their translation. miRNAs may have an impact on cell differentiation, proliferation, and survival, and their deregulation can be inclined to diseases and cancers, including thyroid tumors. The purpose of this review is to summarize the existing findings of deregulated miRNAs in different types of thyroid tumors and to exhibit their potential target genes, especially to demonstrate those involved in tumor invasion and metastasis. In addition, new findings of circulating miRNA expression profiles, single nucleotide polymorphism (SNP) in thyroid tumors, and the correlation of somatic mutations with deregulated miRNA expression in thyroid tumors were all included in this review.  相似文献   

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miRNA是一类高度保守的非编码RNA,为21-25nt的单链型RNA(ssRNAs),由70-90nt的可形成发夹状的内源性转录前体pri-miRNA加工而成,miRNA与靶mRNA的3'-UTR碱基配对,通过抑制mRNA的翻译或直接使mRNA降解,在转录后水平使基因产生沉默,研究发现人类全部基因的三分之一都受到miRNA的调控,这表明miRNA分子实际上是基因调控网络中的核心成分。近来研究发现miRNA与人类的某些疾病密切相关。文章综述了miRNA的基因调控原理和临床研究进展。  相似文献   

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RNA interference (RNAi) is considered as a potential modality for clinical treatment and anti-virus animal breeding. Here, we investigate the feasibility of inhibiting classical swine fever virus (CSFV) replication by short hairpin RNA (shRNA) in vitro and in vivo. We generate four different shRNA-positive clonal cells and two types of shRNA-transgenic pigs. CSFV could be effectively inhibited in shRNA-positive clonal cells and tail tip fibroblasts of shRNA-transgenic pigs. Unexpectedly, an early lethality due to shRNA is observed in these shRNA-transgenic pigs. With further research on shRNA-positive clonal cells and transgenic pigs, we report a great induction of interferon (IFN)-responsive genes in shRNA-positive clonal cells, altered levels of endogenous microRNAs (miRNA), and their processing enzymes in shRNA-positive cells. What is more, abnormal expressions of miRNAs and their processing enzymes are also observed in the livers of shRNA-transgenic pigs, indicating saturation of miRNA/shRNA pathways induced by shRNA. In addition, we investigate the effects of shRNAs on the development of somatic cell nuclear transfer (SCNT) embryos. These results show that shRNA causes adverse effects in vitro and in vivo and shRNA-induced disruption of the endogenous miRNA pathway may lead to the early lethality of shRNA-transgenic pigs. We firstly report abnormalities of the miRNA pathway in shRNA-transgenic animals, which may explain the early lethality of shRNA-transgenic pigs and has important implications for shRNA-transgenic animal preparation.  相似文献   

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野桑蚕是与家蚕亲缘的野生资源,是家蚕遗传进化研究的物质基础,是家蚕品种选育重要的种质资源.秦巴山区是野桑蚕的起源地,独特的地理位置和气候条件,进化形成了丰富的野桑蚕种质类别.初步查明秦巴山区野桑蚕的多态性表现极为丰富,其中有着重大开发利用前景的有三个方向:一是野桑蚕天然有色茧基因的分离和转育;二是野桑蚕抗性基因利用;三是野桑蚕特异性生态变异的研究.  相似文献   

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丝绸是沟通中外文化的使者,古往今来,湖州、杭州、苏州都是众所周知的蚕桑之乡,但不可忽视的是在徽州腹地也有一个古老蚕乡以及蚕乡所孕育的独特地域绚烂文化。  相似文献   

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蚕病是蚕业生产面临的重大威胁之一,因而蚕病的防治显得尤为重要.在分析蚕病发生原因的基础上,认为蚕农的环境意识较差是蚕病发生的重要原因,并根据现状探讨了提高蚕农环境意识的有效途径.  相似文献   

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以湖桑32号桑品种为对照,于2009—2011年,对四川省凉山州不同桑树品种嘉陵20号、南叶1号、云桑2号进行了连续3年的桑叶主要生化指标与养蚕饲育效率的相关性研究。研究表明:以桑品种嘉陵20号粗蛋白含量最高,养蚕饲育效率最好;云桑2号和南叶1号桑品种的粗蛋白含量差异不大,饲育效率也较为接近,参试品种的粗蛋白含量和饲育效率明显高于对照。研究还表明,不同品种桑叶中粗蛋白的含量与养蚕的饲育效率呈明显的正相关关系。  相似文献   

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INTRODUCTIONInsectpostembryonicdevelopmentconsistsofgrowthpunctuatedbyaseriesofmoltsfollowedbymetamorphosis.Thesemoltsandmetamor phosisareinitiatedandcoordinatedbyhormones(Riddiford ,1 994 ) .Itisgenerallyacceptedthattheinterplayofecdysteriods,agroupofstero…  相似文献   

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Based on bioinformatic analysis, we selected two novel microRNAs (miRNAs), bmo-miR-0001 and bmomiR-0015, from high-throughput sequencing of the Bombyx mori larval posterior silk gland (PSG). Firstly, we examined the expression of bmo-miR-0001 and bmo-miR-0015 in 12 different tissues of the 5th instar Day-3 larvae of the silkworm. The results showed that the expression levels of both bmo-miR-0001 and bmo-miR-0015 were obviously higher in the PSG than in other tissues, implying there is a spatio-temporal condition for bmo-miR-0001 and bmo-miR-0015 to regulate the expression of BmFib-L. To test this hypothesis, we constructed pri-bmo-miR-0001 expressing the plasmid pcDNA3.0 [ie1-egfp-pri-bmo-miR-0001-SV40] and pri-bmo-miR-0015 expressing the plasmid pcDNA3.0 [ie1-egfp-pribmo-miR-0015-SV40]. Finally, the BmN cells were harvested and luciferase activity was detected. The results showed that luciferase activity was reduced significantly (P<0.05) in BmN cells co-transfected by pcDNA3.0 [ie1-egfp-pri-bmomiR-0001-SV40] or pcDNA3.0 [ie1-egfp-pri-bmo-miR-0015-SV40] with pGL3.0 [A3-luc-Fib-L-3′UTR-SV40], suggesting that both bmo-miR-0001 and bmo-miR-0015 can down-regulate the expression of BmFib-L in vitro.  相似文献   

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To investigate the effects of hypoxic exercise training on microRNA (miRNA) expression and the role of miRNA expression in regulating lipid metabolism, 20 dietary-induced obese SD rats were divided into a normoxic sedentary group (N, n=10) and a hypoxic exercise training group (H, n=10). After four weeks, measurements were taken of body weight, body length, fat mass, serum lipid concentration, miRNAs differentially expressed in rat liver, and gene and protein expression levels of peroxisome proliferator activated receptor α (PPARα), fatty acid synthetase (FAS), and carnitine palmitoyl transferase 1A (CPT1A) in rat liver. Body weight, Lee’s index, fat mass, fat/weight ratio, and serum levels of total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C) were all significantly lower in the H group than in the N group (P<0.01). Six miRNAs expressed significantly differently in the liver (P<0.05). Specifically, expression levels of miR-378b were significantly lower in the H group than in the N group (P<0.05). Compared with the normoxic sedentary group, hypoxic exercise training resulted in a lower ratio of FAS mRNA to CPT1A mRNA (P<0.05), as well as lower CPT1A protein levels (P<0.01), while a higher ratio of FAS to CPT1A protein levels (P<0.01) was observed. In conclusion, hypoxic training may elevate the resistance of high fat diet induced obesity in rats by reducing the expression of miR-378b, and decrease the fatty acid mitochondrial oxidation in obese rat livers by decreasing the protein expression of CPT1A and increasing the protein expression ratio of FAS/CPT1A.  相似文献   

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目的:建立一种定量、简单、快速、敏感的微小RNA(miRNA,miR)检测方法,并用其观察一些病理状态下有关miRNA的变化.方法:通过特殊设计的茎环结构的反转录引物,对miRNA进行反转录,然后用相应miRNA的正反向引物对该miRNA进行定量检测,观察重复性和特异性.用此法检测了人巨细胞病毒(HCMV)对滋养细胞(HPT-8)细胞内miR-513表达水平的影响,也检测了结直肠癌组织miR-145水平.结果:用该法扩增miRNA特异性强,结果重复性好,该法检测到HCMV感染对miR-513表达的梯度效应.也发现癌组织和正常组织间miR-145的表达有明显的差异.结论:用荧光定量PCR可以对微小RNA快速有效的检测,在临床工作中可得到很好的应用.  相似文献   

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蚕桑教育在清末备受重视,蚕桑学堂、蚕桑讲习所、蚕桑传习所以及设有蚕业专科的农业学堂纷纷设立,清末的蚕桑教育取得了令人瞩目的进展.清末蚕桑教育的兴办,为各地培养了大批懂得近代蚕桑技术的专门人才,促进了各地蚕桑新知识技术的推广和传播,推动了蚕桑业的改良和发展.  相似文献   

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