• 제목/요약/키워드: Real-time quantitative PCR

검색결과 760건 처리시간 0.031초

Establishment of Quantitative Analysis Method for Genetically Modified Maize Using a Reference Plasmid and Novel Primers

  • Moon, Gi-Seong;Shin, Weon-Sun
    • Preventive Nutrition and Food Science
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    • 제17권4호
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    • pp.274-279
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    • 2012
  • For the quantitative analysis of genetically modified (GM) maize in processed foods, primer sets and probes based on the 35S promoter (p35S), nopaline synthase terminator (tNOS), p35S-hsp70 intron, and zSSIIb gene encoding starch synthase II for intrinsic control were designed. Polymerase chain reaction (PCR) products (80~101 bp) were specifically amplified and the primer sets targeting the smaller regions (80 or 81 bp) were more sensitive than those targeting the larger regions (94 or 101 bp). Particularly, the primer set 35F1-R1 for p35S targeting 81 bp of sequence was even more sensitive than that targeting 101 bp of sequence by a 3-log scale. The target DNA fragments were also specifically amplified from all GM labeled food samples except for one item we tested when 35F1-R1 primer set was applied. A reference plasmid pGMmaize (3 kb) including the smaller PCR products for p35S, tNOS, p35S-hsp70 intron, and the zSSIIb gene was constructed for real-time PCR (RT-PCR). The linearity of standard curves was confirmed by using diluents ranging from $2{\times}10^1{\sim}10^5$ copies of pGMmaize and the $R^2$ values ranged from 0.999~1.000. In the RT-PCR, the detection limit using the novel primer/probe sets was 5 pg of genomic DNA from MON810 line indicating that the primer sets targeting the smaller regions (80 or 81 bp) could be used for highly sensitive detection of foreign DNA fragments from GM maize in processed foods.

A Real-Time PCR Assay for the Quantitative Detection of Ralstonia solanacearum in Horticultural Soil and Plant Tissues

  • Chen, Yun;Zhang, Wen-Zhi;Liu, Xin;Ma, Zhong-Hua;Li, Bo;Allen, Caitilyn;Guo, Jian-Hua
    • Journal of Microbiology and Biotechnology
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    • 제20권1호
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    • pp.193-201
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    • 2010
  • A specific and rapid real-time PCR assay for detecting Ralstonia solanacearum in horticultural soil and plant tissues was developed in this study. The specific primers RSF/RSR were designed based on the upstream region of the UDP-3-O-acyl-GlcNAc deacetylase gene from R. solanacearum, and a PCR product of 159 bp was amplified specifically from 28 strains of R. solanacearum, which represent all genetically diverse AluI types and all 6 biovars, but not from any other nontarget species. The detection limit of $10^2\;CFU/g$ tomato stem and horticultural soil was achieved in this real-time PCR assay. The high sensitivity and specificity observed with field samples as well as with artificially infected samples suggested that this method might be a useful tool for detection and quantification of R. solanacearum in precise forecast and diagnosis.

Validation of Reference Genes for Quantitative Real-Time PCR in Bovine PBMCs Transformed and Non-transformed by Theileria annulata

  • Zhao, Hongxi;Liu, Junlong;Li, Youquan;Yang, Congshan;Zhao, Shuaiyang;Liu, Juan;Liu, Aihong;Liu, Guangyuan;Yin, Hong;Guan, Guiquan;Luo, Jianxun
    • Parasites, Hosts and Diseases
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    • 제54권1호
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    • pp.39-46
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    • 2016
  • Theileria annulata is a tick-borne intracellular protozoan parasite that causes tropical theileriosis, a fatal bovine lymphoproliferative disease. The parasite predominantly invades bovine B lymphocytes and macrophages and induces host cell transformation by a mechanism that is not fully comprehended. Analysis of signaling pathways by quantitative real-time PCR (qPCR) could be a highly efficient means to understand this transformation mechanism. However, accurate analysis of qPCR data relies on selection of appropriate reference genes for normalization, yet few papers on T. annulata contain evidence of reference gene validation. We therefore used the geNorm and NormFinder programs to evaluate the stability of 5 candidate reference genes; 18S rRNA, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ACTB (${\beta}-actin$), PRKG1 (protein kinase cGMP-dependent, type I) and TATA box binding protein (TBP). The results showed that 18S rRNA was the reference gene most stably expressed in bovine PBMCs transformed and non-transformed with T. annulata, followed by GAPDH and TBP. While 18S rRNA and GAPDH were the best combination, these 2 genes were chosen as references to study signaling pathways involved in the transformation mechanism of T. annulata.

A Field Deployable Real-Time Loop-Mediated Isothermal Amplification Targeting Five Copy nrdB Gene for the Detection of 'Candidatus Liberibacter asiaticus' in Citrus

  • Tirumalareddy Danda;Jong-Won Park;Kimberly L. Timmons;Mamoudou Setamou;Eliezer S. Louzada;Madhurababu Kunta
    • The Plant Pathology Journal
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    • 제39권4호
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    • pp.309-318
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    • 2023
  • Huanglongbing (HLB) is one of the most destructive diseases in citrus, which imperils the sustainability of citriculture worldwide. The presumed causal agent of HLB, 'Candidatus Liberibacter asiaticus' (CLas) is a non-culturable phloem-limited α-proteobacterium transmitted by Asian citrus psyllids (ACP, Diaphorina citri Kuwayama). A widely adopted method for HLB diagnosis is based on quantitative real-time polymerase chain reaction (qPCR). Although HLB diagnostic qPCR provides high sensitivity and good reproducibility, it is limited by time-consuming DNA preparation from plant tissue or ACP and the requirement of proper lab instruments including a thermal cycler to conduct qPCR. In an attempt to develop a quick assay that can be deployed in the field for CLas detection, we developed a real-time loop-mediated isothermal amplification (rt-LAMP) assay by targeting the CLas five copy nrdB gene. The rt-LAMP assay using various plant sample types and psyllids successfully detected the nrdB target as low as ~2.6 Log10 copies. Although the rt-LAMP assay was less sensitive than laboratory-based qPCR (detection limit ~10 copies), the data obtained with citrus leaf and bark and ACP showed that the rt-LAMP assay has >96% CLas detection rate, compared to that of laboratory-based qPCR. However, the CLas detection rate in fibrous roots was significantly decreased compared to qPCR due to low CLas titer in some root DNA sample. We also demonstrated that the rt-LAMP assay can be used with a crude leaf DNA extract which is fully deployable in the field for quick and reliable HLB screening.

Quantitative Real-Time PCR Assay for Detection of Paenibacillus polymyxa Using Membrane-Fusion Protein-Based Primers

  • Cho, Min Seok;Park, Dong Suk;Lee, Jung Won;Chi, Hee Youn;Sohn, Soo-In;Jeon, Bong-Kyun;Ma, Jong-Beom
    • Journal of Microbiology and Biotechnology
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    • 제22권11호
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    • pp.1575-1579
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    • 2012
  • Paenibacillus polymyxa is known to be a plant-growth-promoting rhizobacterium. The present study describes a quantitative polymerase chain reaction (qPCR) assay for the specific detection and quantitation of P. polymyxa using a primer pair based on the sequence of a membrane-fusion protein for the amplification of a 268 bp DNA fragment. This study reports that the qPCR-based method is applicable for the rapid and sensitive detection of P. polymyxa and can be used as an alternative method for agricultural soil monitoring.

인간 대장암 세포주에서 sulindac sulfide 처리에 의해 차별적으로 발현되는 유전자 군의 분석 (Analysis of Differentially Expressed Genes by Sulindac Sulfide in Human Colorectal Cells)

  • 신승화;김종식
    • 생명과학회지
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    • 제17권7호통권87호
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    • pp.996-1001
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    • 2007
  • 본 연구에서는 NSAID계 약물인 sulindac, sulindac sulfone, 그리고 sulindac sulfide 처리에 의한 암세포 생존율에 미치는 영향을 확인하기 위하여, 인간 대장암 세포주인 HCTl16에 각각 10 ${\mu}M$의 NSAID들을 처리하였다. 처리한약물 중 sulindac sulfide에 의한 암세포 생존율이 가장 높게 감소하는 것으로 MTS assay 결과 확인되었다. 또한 sulindac sulfide의 처리 농도가 증가됨에 따라 세포 생존율이 감소하는 것으로 확인되었다. Sulindac sulfide의 처리에 따른 이러한 암 세포 사멸의 분자생물학적 기전을 이해하기 위하여, oligo DNA microarray 실험을 수행하였다. 그 결과, 10 ${\mu}M$의 sulindac sulfide의 처리에 의해 2배 이상 발현이 증가되는 유전자가 23개 확인되었고, 반대로 2배 이상 발현이 감소되는 유전자가 33개 확인되었다. 증가되는 유전자중 3개(NAG-1, DDIT3, PCK2)를 선택하여, RT-PCR과 real-time PCR을 수행하였다. 그 결과 두 실험 모두 DNA microarray 실험결과와 동일하게 발현이 증가되었다. 이 중 sulindac, sulindac sulfone, sulindac sulfide에 의 한 NAG-1 유전자의 발현변화를 RT-PCR과 real-time PCR 방법으로 확인한 결과, sulindac sulfide에 의한 암 억제유전자인 NAG-1의 발현이 가장 많이 발현되었다. 이러한 연구결과는 세포생존율 결과와 비교하였을 때, NAG-1의 높은 발현과 암 세포 생존율의 감소가 관련이 있음을 간접적으로 시사한다. 따라서 이들 연구결과는 sulindac sulfide에 의한 화학적 암 예방법의 분자생물학적 기전을 이해하는데 도움을 줄 것으로 생각한다.

Tissue-specific gene expression analysis of silkworm (Bombyx mori) by quantitative real-time RT-PCR

  • Park, Seung-Won;Kang, Seok-Woo;Goo, Tae-Won;Kim, Seong-Ryul;Lee, Gwang-Gill;Paik, Soon-Young
    • BMB Reports
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    • 제43권7호
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    • pp.480-484
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    • 2010
  • The Bombyx mori Microarray Database (BmMDB; http://silkworm.swu.edu.cn/microarray) provides information for tissue-specific gene expression by using the whole-genome oligonucleotide microarray in the silkworm. We analyzed the tissue-specific expression patterns in the silk gland, fat body, and midgut five days of fifth instar larvae during the development of B. mori. To verify the tissue-specific expression, analysis was conducted using quantitative Real-time RT-PCR and the highly expressed endogenous Actin RNA as an intrinsic reference. Finally, we confirmed five genes, (sw15872, sw00692, sw20990, sw05300,and sw2250), out of 18 candidates expressed in two different tissues, which was consistent with the data published by Dr. Xiang's group, thereby supporting the BmMDB. Further studies for promoter regions of candidate genes can be applied in creating transgenic silkworms as biomedical insects for use in producing biomaterials, and to serve as well-characterized models for understanding the mechanism for the genetic regulation of tissue-specific development.

Cytokine expression pattern in milk somatic cells of subclinical mastitis-affected cattle analyzed by real time PCR

  • Bhatt, Vaibhav D.;Khade, Prasad S.;Tarate, Sagar B.;Tripathi, Ajai K.;Nauriyal, Dev S.;Rank, Dharamshi N.;Kunjadia, Anju P.;Joshi, Chaitanya G.
    • 대한수의학회지
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    • 제52권4호
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    • pp.231-238
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    • 2012
  • The expression profiles of inflammatory cytokines viz. interleukins (IL)-6, IL-8, IL-12, granulocyte macrophage-colony stimulating factor, interferon-${\gamma}$ and tumor necrosis factor-${\alpha}$ in response to subclinical mastitis in indigenous cattle breed Kankrej (n = 6), Gir (Bos indicus) (n = 12) and crossbred (Bos taurus${\times}$Bos indicus) (n = 7) were investigated using quantitative real time PCR. Significant correlation (p < 0.05) was observed between total bacterial load and somatic cell count (SCC) in all three breeds of cattle. All the cytokines were observed to be up-regulated compared to cows with healthy quarters, however, level of their expression varied among three breeds of cattle. In Kankrej most cytokines were found to be transcribed to higher levels than in other two breeds; the milk had higher load of bacteria but not so high SCC, implying that Kankrej has a higher inherent resistance against mastitis. The results of present study indicated that mammary glands of crossbred cattle are more sensitive to bacterial infection than indigenous breed of cattle as they elicit immune response at lower bacterial load and result into higher SCC. Research on identification of factors responsible for differentially expressed cytokines profiles and use of cytokines as immunomodulatory tools can pave way for formulating control strategies against bovine mastitis.

Selection of Reliable Reference Genes for Real-time qRT-PCR Analysis of Zi Geese (Anser anser domestica) Gene Expression

  • Ji, Hong;Wang, Jianfa;Liu, Juxiong;Guo, Jingru;Wang, Zhongwei;Zhang, Xu;Guo, Li;Yang, Huanmin
    • Asian-Australasian Journal of Animal Sciences
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    • 제26권3호
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    • pp.423-432
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    • 2013
  • Zi geese (Anser anser domestica) belong to the white geese and are excellent layers with a superior feed-to-egg conversion ratio. Quantitative gene expression analysis, such as Real-time qRT-PCR, will provide a good understanding of ovarian function during egg-laying and consequently improve egg production. However, we still don't know what reference genes in geese, which show stable expression, should be used for such quantitative analysis. In order to reveal such reference genes, the stability of seven genes were tested in five tissues of Zi geese. Methodology/Principal Findings: The relative transcription levels of genes encoding hypoxanthine guanine phosphoribosyl transferase 1 (HPRT1), ${\beta}$-actin (ACTB), ${\beta}$-tubulin (TUB), glyceraldehyde-3-phosphate-dehydrogenase (GADPH), succinate dehydrogenase flavoprotein (SDH), 28S rRNA (28S) and 18S rRNA (18S) have been quantified in heart, liver, kidney, muscle and ovary in Zi geese respectively at different developmental stages (1 d, 2, 4, 6 and 8 months). The expression stability of these genes was analyzed using geNorm, NormFinder and BestKeeper software. Conclusions: The expression of 28S in heart, GAPDH in liver and ovary, ACTB in kidney and HPRT1 in muscle are the most stable genes as identified by the three different analysis methods. Thus, these genes are recommended for use as candidate reference genes to compare mRNA transcription in various developmental stages of geese.

한국인의 임플란트 주위 질환에서 real time PCR법을 이용한 치주세균 평가: pilot study (Evaluation of periopathogenic bacteria of peri-implantitis using real-time PCR in Koreans: pilot study)

  • 이문영;권은영;김현주;이주연;주지영
    • 구강회복응용과학지
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    • 제34권3호
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    • pp.186-195
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    • 2018
  • 목적: 한국인에서 임플란트 주위 질환의 심도에 따른 미생물학적 차이를 알아보기 위해 real time Polymerase Chain Reaction(real-time PCR)법을 이용하여 5종의 치주세균의 정량적, 정성적 분석을 시행하였다. 연구 재료 및 방법: 임플란트가 식립된 총 60명의 환자를 치근단 방사선 사진 및 임상지수 검사를 통해 3군(건강군, 임플란트 주위 점막염군, 임플란트 주위염군)으로 나누었다. 멸균된 curette기구를 이용해 치은연하에서 미생물 샘플을 채취한 후 치주세균 5종에 관해 real time PCR을 시행하였고 comparative delta-CT method를 이용하여 분석한 후 미생물의 상대적 발현량을 비교하였다. 결과: Eikenella corrodens, Treponema denticola의 상대적 발현량은 임플란트 주위염 그룹에서 유의하게 높게 나타났다(P < 0.017). 반면 Fusobacterium nucleatum, Porphyromonas gingivalis의 상대적 발현량은 질환의 심도와는 관련 없이 건강한 임플란트 그룹에서 가장 높게 나타났다. Prevotella intermedia의 상대적 발현량은 건강한 임플란트 그룹에서 유의하게 낮게 나타났다(P < 0.017). 결론: 한국인의 임플란트 주위질환에서 대표적인 치주염 세균이 검출되었으나 치주염과 유사한 미생물학적 분포를 보이지는 않았다.