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BackgroundQuantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) is a sensitive technique for quantifying gene expression levels. One or more appropriate reference genes must be selected to accurately compare mRNA transcripts across different samples and tissues. Thus far, only actin-2 has been used as a reference gene for qRT-PCR in chicory, and a full comparison of several candidate reference genes in chicory has not yet been reported.ResultsSeven candidate reference genes, including nicotinamide adenine dinucleotide dehydrogenase (NADHD), actin (ACT), β-tubulin (TUB), glyceraldehyde-3-phosphate-dehydrogenase (GADPH), histone H3 (H3), elongation factor 1-alpha (EF) and 18S rRNA (rRNA) were selected to study the expression stability for normalisation of gene expression in chicory. Primer specificity and amplification efficiency were verified for each gene. The expression stability of these genes was analysed across chicory root and leaf tissues using geNorm, NormFinder and BestKeeper software. ACT, EF, and rRNA were the most stable genes as identified by the three different analysis methods. In addition, the use of ACT, EF and GAPDH as reference genes was illustrated by analysing 1-FEHII (FEHII) expression in chicory root and leaf tissues. These analyses revealed the biological variation in FEHII transcript expression among the tissues studied, and between individual plants.ConclusionsgeNorm, NormFinder, and BestKeeper analyses indicated that ACT, EF and rRNA had the highest expression stability across leaf and root tissues, while GAPDH and NADHD showed relatively low expression stability. The results of this study emphasise the importance of validating reference genes for qRT-PCR analysis in chicory. The use of the most stable reference genes such as ACT and EF allows accurate normalisation of gene expression in chicory leaf and root tissues.

Genetically modified plants, in the following referred to as genetically modified organisms or GMOs, have been commercially grown for almost two decades. In 2010 approximately 10% of the total global crop acreage was planted with GMOs (James, 2011). More than 30 countries have been growing commercial GMOs, and many more have performed field trials. Although the majority of commercial GMOs both in terms of acreage and specific events belong to the four species: soybean, maize, cotton and rapeseed, there are another 20+ species where GMOs are commercialized or in the pipeline for commercialization. The number of GMOs cultivated in field trials or for commercial production has constantly increased during this time period. So have the number of species, the number of countries involved, the diversity of novel (added) genetic elements and the global trade. All of these factors contribute to the increasing complexity of detecting and correctly identifying GMO derived material. Many jurisdictions, including the European Union (EU), legally distinguish between authorized (and therefore legal) and un-authorized (and therefore illegal) GMOs. Information about the developments, field trials, authorizations, cultivation, trade and observations made in the official GMO control laboratories in different countries around the world is often limited, despite several attempts such as the OECD BioTrack for voluntary dissemination of data. This lack of information inevitably makes it challenging to detect and identify GMOs, especially the un-authorized GMOs. The present paper reviews the state of the art technologies and approaches in light of coverage, practicability, sensitivity and limitations. Emphasis is put on exemplifying practical detection of un-authorized GMOs. Although this paper has a European (EU) bias when examples are given, the contents have global relevance.

Superoxide dismutases (SODs) are metalloproteins that catalyse the dismutation of superoxide radicals to oxygen and hydrogen peroxide. The enzyme has been found in all aerobic organisms examined, where it plays a major role in the defence against toxic reduced oxygen species which are generated in many biological oxidations. Here we report the complete primary structure of a plant manganese superoxide dismutase (MnSOD), deduced from a cDNA clone of Nicotiana plumbaginifolia. The plant protein is highly homologous to MnSODs from other organisms and also contains an N‐terminal leader sequence resembling a transit peptide for mitochondrial targeting. The location of the mature protein within the mitochondria has been demonstrated by subcellular fractionation experiments. We have analysed the expression profile of this MnSOD and found that it is dramatically induced during stress conditions, most notably in tissue culture as a result of sugar metabolism and also as part of the pathogenesis response of the plant, being induced by ethylene, salicylic acid, and Pseudomonas syringae infection. This induction is always accompanied by an increase in cytochrome oxidase activity, which suggests a specific protective role for MnSOD during conditions of increased mitochondrial respiration.

In this article we describe the isolation and characterisation of the junction between insert DNA and plant DNA in the transgenic Roundup Ready soybean line event 40-3-2. Our results establish that during integration of the insert DNA several rearrangements occurred at the 3' NOS junction and that the genomic plant DNA at the pre-integration site may have been rearranged. These findings highlight the utility of characterising junction regions to fulfil the request for information regarding which DNA sequences have been incorporated in commercialised transgenic lines. Furthermore, the characterisation of junction regions is, in our opinion, the method of choice to support method development for detection and identification of plant biotechnology-derived products