Electroporation of rapeseed protoplasts - transient and stable transformation

A convenient, rapid and efficient method for establishing transgenic lines of Brassica napus

BACKGROUND

Brassica napus is an important oilseed crop that offers a considerable amount of biomass for global vegetable oil production. The establishment of an efficient genetic transformation system with a convenient transgenic-positive screening method is of great importance for gene functional analysis and molecular breeding. However, to our knowledge, there are few of the aforementioned systems available for efficient application in B. napus.

RESULTS

Based on the well-established genetic transformation system in B. napus, five vectors carrying the red fluorescence protein encoding gene from Discosoma sp. (DsRed) were constructed and integrated into rapeseed via Agrobacterium-mediated hypocotyl transformation. An average of 59.1% tissues were marked with red fluorescence by the visual screening method in tissue culture medium, 96.1% of which, on average, were amplified with the objective genes from eight different rapeseed varieties. In addition, the final transgenic-positive efficiency of the rooted plantlets reached up to 90.7% from red fluorescence marked tissues, which was much higher than that in previous reports. Additionally, visual screening could be applicable to seedlings via integration of DsRed, including seed coats, roots, hypocotyls and cotyledons during seed germination. These results indicate that the highly efficient genetic transformation system combined with the transgenic-positive visual screening method helps to conveniently and efficiently obtain transgenic-positive rapeseed plantlets.

CONCLUSION

A rapid, convenient and highly efficient method was developed to obtain transgenic plants, which can help to obtain the largest proportion of transgene-positive regenerated plantlets, thereby avoiding a long period of plant regeneration. The results of this study will benefit gene functional studies especially in high-throughput molecular biology research.

Engineering Multiple Abiotic Stress Tolerance in Canola, Brassica napus

Impacts of climate change like global warming, drought, flooding, and other extreme events are posing severe challenges to global crop production. Contribution of Brassica napus towards the oilseed industry makes it an essential component of international trade and agroeconomics. Consequences from increasing occurrences of multiple abiotic stresses on this crop are leading to agroeconomic losses making it vital to endow B. napus crop with an ability to survive and maintain yield when faced with simultaneous exposure to multiple abiotic stresses. For an improved understanding of the stress sensing machinery, there is a need for analyzing regulatory pathways of multiple stress-responsive genes and other regulatory elements such as non-coding RNAs. However, our understanding of these pathways and their interactions in B. napus is far from complete. This review outlines the current knowledge of stress-responsive genes and their role in imparting multiple stress tolerance in B. napus. Analysis of network cross-talk through omics data mining is now making it possible to unravel the underlying complexity required for stress sensing and signaling in plants. Novel biotechnological approaches such as transgene-free genome editing and utilization of nanoparticles as gene delivery tools are also discussed. These can contribute to providing solutions for developing climate change resilient B. napus varieties with reduced regulatory limitations. The potential ability of synthetic biology to engineer and modify networks through fine-tuning of stress regulatory elements for plant responses to stress adaption is also highlighted.