20 research outputs found
A GG Nucleotide Sequence of the 3′ Untranslated Region of Amyloid Precursor Protein mRNA Plays a Key Role in the Regulation of Translation and the Binding of Proteins
The alternative polyadenylation of the mRNA encoding the amyloid precursor protein (APP) involved in Alzheimer's disease generates two molecules, with the first of these containing 258 additional nucleotides in the 3′ untranslated region (3′UTR). We have previously shown that these 258 nucleotides increase the translation of APP mRNA injected in Xenopus oocytes (5). Here, we demonstrate that this mechanism occurs in CHO cells as well. We also present evidence that the 3′UTR containing 8 nucleotides more than the short 3′UTR allows the recovery of an efficiency of translation similar to that of the long 3′UTR. Moreover, the two guanine residues located at the 3′ ends of these 8 nucleotides play a key role in the translational control. Using gel retardation mobility shift assay, we show that proteins from Xenopus oocytes, CHO cells, and human brain specifically bind to the short 3′UTR but not to the long one. The two guanine residues involved in the translational control inhibit this specific binding by 65%. These results indicate that there is a correlation between the binding of proteins to the 3′UTR of APP mRNA and the efficiency of mRNA translation, and that a GG motif controls both binding of proteins and translation
SYBR®Green qPCR screening methods for the presence of "35S promoter" and "NOS terminator" elements in food and feed products400
The Cauliflower Mosaic Virus "35S promotor" (p35S) and the Agrobacterium "Nopaline Synthase" terminator (tNOS) are the most represented generic recombinant elements in commercial genetically modified crops to date. A set of four new SYBR</p
Four new SYBR®Green qPCR screening methods for the detection of Roundup Ready(r), LibertyLink(r), and CryIAb traits in genetically modified products362
SYBR(r)Green qPCR methods for the detection of the Roundup Ready (r) "CP4-EPSPS", LibertyLink (r) "PAT" and "BAR" and the Bacillus thuringiensis "CryIAb" traits as present in genetically modified organisms (GMO) were developed. Their specificity, sensitivity, and PCR method efficiency were determined. All methods are specific and generate amplicons of 108, 73, 109, and 69 bp, respectively, for "CP4-EPSPS", "CryIAb", "PAT" and "BAR" targets. They perform well at low target levels and can detect down to 5 copies of their respective targets extracted from a sample. The PCR efficiency of the methods ranges between 91 and 109%. Due to their trait-specific nature, these methods allow an efficient screening between the different GMO. In this way, the number of possible GMO candidates present in a sample can be reduced what results in lower global costs due to limiting of further the number of analytical identification steps. The application of these methods in CoSYPS GMO analysis is illustrated using two GEMMA proficiency test samples and a reference material from the GM rapeseed event RF3. This set of SYBR(r)Green qPCR trait-specific methods represents a very interesting novel set of GMO analysis methods allowing cost-effective identification of GM materials in products.</p
SYBR®Green qPCR methods for detection of endogenous reference genes in commodity crops: a step ahead in combinatory screening of Genetically Modified Crops in food and feed products
Identification of crops present in food and/or feed matrices represents an important step in the screening strategies targeting genetically modified organisms (GMO). Soybean, maize, oilseed rape, rice, cotton, sugar beet and potato are to date the most important sources of genetically modified materials imported in the European Union (EU). In order to allow detection of their presence in an integrated screening approach, a set of SYBR-«Green real-time polymerase chain reaction (qPCR) methods has been developed which can be used under the same assay conditions and at similar efficiency for each of the abovementioned crops. Each qPCR method is shown to meet the performance criteria (i.e. specificity, limit of detection and PCR efficiency) set by the European Network of GMO Laboratories (ENGL). When combined with the equivalent qPCR methods targeting GMO elements, these crop-specific SYBR-«Green qPCR methods can aid the development of an efficient tool for determining GMO presence in food and/or feed products</p
Detection of genetically modified plant products by protein strip testing: An evaluation of real-life samples
The determination of the presence of genetically modified plant material by the detection of expressed genetically engineered proteins using lateral flow protein strip tests has been evaluated in different matrices. The presence of five major genetically engineered proteins (CP4-EPSPS, CryIAb, Cry9C, PAT/pat and PAT/bar protein) was detected at low levels in seeds, seed/leaf powder and leaf tissue from genetically modified soy, maize or oilseed rape. A comparison between "protein strip test" (PST) and "polymerase chain reaction" (PCR) analysis of genetically modified food/feed samples demonstrates complementarities of both techniques. -® Springer-Verlag 2007</p
SYBR Green qPCR methods for detection of endogenous reference genes in commodity crops: a step ahead in combinatory screening of genetically modified crops in food and feed products
Identification of crops present in food and/or
feed matrices represents an important step in the screening
strategies targeting genetically modified organisms
(GMO). Soybean, maize, oilseed rape, rice, cotton, sugar
beet and potato are to date the most important sources of
genetically modified materials imported in the European
Union (EU). In order to allow detection of their presence in
an integrated screening approach, a set of SYBRGreen
real-time polymerase chain reaction (qPCR) methods has
been developed which can be used under the same assay
conditions and at similar efficiency for each of the
abovementioned crops. Each qPCR method is shown to
meet the performance criteria (i.e. specificity, limit of
detection and PCR efficiency) set by the European Network
of GMO Laboratories (ENGL). When combined with
the equivalent qPCR methods targeting GMO elements,
these crop-specific SYBRGreen qPCR methods can aid
the development of an efficient tool for determining GMO
presence in food and/or feed products.JRC.I.4-Molecular biology and genomic