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Brassica napus cultivars have little or no primary dormancy; however, they are prone to secondary dormancy induction. Secondary dormant seeds can produce volunteer plants, which can result in genetic contamination, reduced quality and biosafety issues. However, information regarding the molecular mechanism underlying secondary dormancy is limited. The MOTHER OF FT AND TFL1 (MFT) gene, which is evolutionarily conserved in the plant kingdom, acts in a complex gene network in the seed dormancy or germination processes. In this study, we identified four B. napus genes that share high homology with AtMFT, named as BnaMFT. Analyses of cis-acting elements showed that BnaMFT promoters contain multiple seed-specific regulatory elements, and various stress- and hormone-responsive elements. Further experiments validated that BnaMFTs were specifically expressed during seed maturation and in the dry seed, with peaks at 35–42 days after pollination. BnaMFTs were not sufficient for primary dormancy; however, they were significantly enhanced by secondary dormancy induction with PEG6000 treatment. Moreover, BnaMFT transcripts were elevated by treatment with abscisic acid (ABA), which is known to be accumulated during secondary dormancy. These results collectively suggest that increased BnaMFT transcription levels are associated with secondary dormancy induction in an ABA-dependent manner in B. napus.

Development of new technologies for evaluating genetically modified (GM) crops has revealed that there are unintended insertions and expression changes in GM crops. Profiling techniques are non-targeted approaches and are capable of detecting more unintended changes in GM crops. Here, we report the application of a comparative proteomic approach to investigate the protein profile differences between a GM rice line, which has a lysine-rich protein gene, and its non-transgenic parental line. Proteome analysis by two-dimensional gel electrophoresis (2-DE) and mass spectrum analysis of the seeds identified 22 differentially expressed protein spots. Apart from a number of glutelins that were detected as targeted proteins in the GM line, the majority of the other changed proteins were involved in carbohydrate metabolism, protein synthesis and stress responses. These results indicated that the altered proteins were not associated with plant allergens or toxicity.