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Contains fulltext : 289962.pdf (Publisher’s version ) (Open Access) 24 p.

Brief Communication Enhancing the accumulation of eicosapentaenoic acid and docosahexaenoic acid in transgenic Camelina through the CRISPR-Cas9 inactivation of the competing FAE1 pathway

There is a growing recognition of the challenges associated with ensuring good nutrition for all without compromising the environment. This is particularly true for aquaculture, given the reliance on marine extraction for key feed ingredients, yet at the same time it delivers key nutrients such as omega-3 long chain polyunsaturated fatty acids. This review will consider progress in transitioning away from oceanic-derived fish oils as feed ingredients, focusing on the emerging transgenic plant sources of these fatty acids. Specific consideration is given to the "validation" phase of this process, in which oils from GM plants are used as substitutes for bona fide fish oils in aquafeed diets. Equally, consideration is given to the demonstration of "real-world" potential by GM field trials. Collectively, the status of these new plant-based sources of omega-3 fish oils confirm the arrival of a new wave of plant biotech products, 25 years after the introduction of herbicide-tolerant input traits and demonstrate the power of GM agriculture to contribute to food security and operating within planetary boundaries.

International Sign (IS) interpreting at conferences has been slowly becoming more common over recent decades, while still new within international institutions. However, little is known about IS interpreting. The few studies to date indicate that IS interpreting requires partly different skills and strategies to interpreting into a national signed language. This chapter reports on a comparative study of interpreting strategies between two teams of interpreters. The study analyses the interpreting strategies of a team of IS interpreters, contrasting them with a team of national sign language interpreters (NGT in this case), and looking specifically at how they prepare for an interpreting assignment. A reflexive thematic analysis shows that their preparation methods are very different: the IS team focuses on creating signed concepts whereas the NGT team primarily discusses terminology and using the correct NGT signs. This study provides further evidence that conference IS interpreting requires specific preparation.

EPA and DHA are required for normal cell function and can also induce health benefits. Oily fish are the main source of EPA and DHA for human consumption. However, food choices and concerns about the sustainability of marine fish stocks limit the effectiveness of dietary recommendations for EPA+DHA intakes. Seed oils from transgenic plants that contain EPA+DHA are a potential alternative source of EPA and DHA. The present study investigated whether dietary supplementation with transgenic Camelina sativa seed oil (CSO) that contained EPA and DHA was as effective as fish oil (FO) in increasing EPA and DHA concentrations when consumed as a dietary supplement in a blinded crossover study. Healthy men and women (n 31; age 53 (20-74) yrs) were randomised to consume 450 mg/day EPA+DHA provided either as either CSO or FO for 8 weeks, followed by 6 weeks washout and then switched to consuming the other test oil. Fasting venous blood samples were collected at the start and end of each supplementation period. Consuming the test oils significantly (P < 0.05) increased EPA and DHA concentrations in plasma triacylglycerol, phosphatidylcholine and cholesteryl esters. There were no significant differences between test oils in the increments of EPA and DHA. There was no significant difference between test oils in the increase in the proportion of erythrocyte EPA+DHA (CSO, 12%; P < 0.0001 and FO, 8%; P = 0.02). Together these findings show that consuming CSO is as effective as FO for increasing EPA and DHA concentrations in humans.

Brachiaria spp. is the most used forage in extensive cattle production in the Central-Western region of Brazil. However, livestock fed with these grasses can develop hepatogenous intoxication due to the presence of steroidal saponins that promote photosensitivity, inefficiency of production in the herds and death. Grass toxicity depends on factors related to animal susceptibility or resistance and intrinsic plant factors, providing significant differences in the clinical manifestation and mortality of livestock. Three experiments were conducted to investigate the adaptation management and inherited resistance to prevent Brachiaria spp. poisoning in sheep. In the first experiment, the adaptive management of lambs was performed, controlling the grazing time in Brachiaria spp. pastures. Groups of sheep grazing previously in Brachiaria decumbens paddocks for 2 h daily or on alternate days for 60 days presented low hepatotoxic changes and had reduced the number of intoxicated lambs when compared to the control group during the challenge. In experiment 2, ruminal transfaunation from adapted adult sheep to non-adapted lambs to grazing on the grass reduced the hepatotoxicity, which suggests that Brachiaria spp. poisoning resistance could be transferred by ruminal fluid to non-adapted animals. In the third experiment, lambs from flocks raised in Brachiaria pastures showed less susceptibility to poisoning than lambs from flocks raised in non-toxic pastures, suggesting inherited resistance to the toxicosis. These results suggest that the control of grazing time combined with transfaunation can be employed to decrease the frequency of poisoning in susceptible flocks. However, a definitive solution in the long-term would be the selection of resistant sheep herds.

International audience; The desaturase FAD2 is the main target for breeding high oleic crops. Plant breeding is based on the recombination of a diversity of alleles to select the optimal combinations for a defined trait. Classical breeding relies on the availability of alleles in natural accessions, but also in the different subgenomes in the case of polyploid crop species like camelina. Screening of selected accessions of camelina identified lines with variable oleic and linoleic acid content. Recombinant lines with specific transgression on these traits were selected in field trials and genome wide sequencing was carried out to identify potential cis or trans-regulation of FAD2 gene. However none of these recombinant lines could compare with camelina mutants obtained by CRISPR-mediated gene editing (1). These lines were for the first time evaluated in the field at Rothamsted research demonstrating the need for agronomical evaluation of edited plants (2). Interestingly, the highest oleic line showed important morphological changes that were environmentally controlled demonstrating the importance of FA desaturation in plant development. Identification of camelina lines with fine tuned ratio of polyunsaturated/monounsaturated content allows precise evaluation of the roles of these fatty acids in the response to abiotic stress. 1. C. Morineau et al., Selective gene dosage by CRISPR-Cas9 genome editing in hexaploid Camelina sativa.

Vectors and transgenic plants containing said nucleic acid sequences