Molecular Regulation of Biosynthesis of Long Chain Polyunsaturated Fatty Acids in Atlantic Salmon

publishedVersio

Utilisation de jeu de langue comme outil de motivation dans l’enseignement et l’apprentissage du français aux écoles secondaires du Ghana : enjeux et perspectives

Résumé : Cette étude porte sur l’utilisation des jeux de langue dans la classe de FLE pour motiver les apprenants ghanéens au niveau secondaire (SHS) du Ghana pour apprendre le français. Pour réussir à notre tâche, nous avons fait une préenquête qui révèle que les apprenants et les enseignants de trois écoles sélectionnées ne ni utilisent pas les jeux pédagogiques dans l’apprentissage et l’enseignement de la langue française. Ils ne connaissent pas même l’importance de l’utilisation des jeux. Basant sur cette observation, nous avons collecté des données dans trois écoles secondaires dans la région Volta du Ghana en utilisant des questionnaires et l’interview. Les données sont analysées par la méthode mixte. L’analyse montre que l’emploi des jeux pédagogiques facilite l’enseignement et l’apprentissage en les rendant plus intéressants et addictifs. À dater de ces observations, nous avons recommandé aux CREF et les autorités chargées de l’apprentissage et l’enseignement de français d’inclure les jeux dans la formation des élèves et les enseignants. Mots-clés : Apprentissage, Enseignement, Français, Jeu, Langue, Motivatio

CRISPR/Cas9-mediated editing of Δ5 and Δ6 desaturases impairs Δ8-desaturation and docosahexaenoic acid synthesis in Atlantic salmon (Salmo salar L.)

The in vivo functions of Atlantic salmon fatty acyl desaturases (fads2), Δ6fads2-a, Δ6fads2-b, Δ6fads2-c and Δ5fads2 in long chain polyunsaturated fatty acid (LC-PUFA) synthesis in salmon and fish in general remains to be elucidated. Here, we investigate in vivo functions and in vivo functional redundancy of salmon fads2 using two CRISPR-mediated partial knockout salmon, Δ6abc/5Mt with mutations in Δ6fads2-a, Δ6fads2-b, Δ6fads2-c and Δ5fads2, and Δ6bcMt with mutations in Δ6fads2-b and Δ6fads2-c. F0 fish displaying high degree of gene editing (50–100%) were fed low LC-PUFA and high LC-PUFA diets, the former containing reduced levels of eicosapentaenoic (20:5n-3) and docosahexaenoic (22:6n-3) acids but higher content of linoleic (18:2n-6) and alpha-linolenic (18:3n-3) acids, and the latter containing high levels of 20:5n-3 and 22:6n-3 but reduced compositions of 18:2n-6 and 18:3n-3. The Δ6abc/5Mt showed reduced 22:6n-3 levels and accumulated Δ6-desaturation substrates (18:2n-6, 18:3n-3) and Δ5-desaturation substrate (20:4n-3), demonstrating impaired 22:6n-3 synthesis compared to wildtypes (WT). Δ6bcMt showed no effect on Δ6-desaturation compared to WT, suggesting Δ6 Fads2-a as having the predominant Δ6-desaturation activity in salmon, at least in the tissues analyzed. Both Δ6abc/5Mt and Δ6bcMt demonstrated significant accumulation of Δ8-desaturation substrates (20:2n-6, 20:3n-3) when fed low LC-PUFA diet. Additionally, Δ6abc/5Mt demonstrated significant upregulation of the lipogenic transcription regulator, sterol regulatory element binding protein-1 (srebp-1) in liver and pyloric caeca under reduced dietary LC-PUFA. Our data suggest a combined effect of endogenous LC-PUFA synthesis and dietary LC-PUFA levels on srebp-1 expression which ultimately affects LC-PUFA synthesis in salmon. Our data also suggest Δ8-desaturation activities for salmon Δ6 Fads2 enzymes.publishedVersio

CRISPR/Cas9-mediated ablation of elovl2 in Atlantic salmon (Salmo salar L.) inhibits elongation of polyunsaturated fatty acids and induces Srebp-1 and target genes

Atlantic salmon can synthesize polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (20:5n-3), arachidonic acid (20:4n-6) and docosahexaenoic acid (22:6n-3) via activities of very long chain fatty acyl elongases (Elovls) and fatty acyl desaturases (Fads), albeit to a limited degree. Understanding molecular mechanisms of PUFA biosynthesis and regulation is a pre-requisite for sustainable use of vegetable oils in aquafeeds as current sources of fish oils are unable to meet increasing demands for omega-3 PUFAs. By generating CRISPR-mediated elovl2 partial knockout (KO), we have shown that elovl2 is crucial for multi-tissue synthesis of 22:6n-3 in vivo and that endogenously synthesized PUFAs are important for transcriptional regulation of lipogenic genes in Atlantic salmon. The elovl2-KOs showed reduced levels of 22:6n-3 and accumulation of 20:5n-3 and docosapentaenoic acid (22:5n-3) in the liver, brain and white muscle, suggesting inhibition of elongation. Additionally, elovl2-KO salmon showed accumulation of 20:4n-6 in brain and white muscle. The impaired synthesis of 22:6n-3 induced hepatic expression of sterol regulatory element binding protein-1 (srebp-1), fatty acid synthase-b, Δ6fad-a, Δ5fad and elovl5. Our study demonstrates key roles of elovl2 at two penultimate steps of PUFA synthesis in vivo and suggests Srebp-1 as a main regulator of endogenous PUFA synthesis in Atlantic salmon.publishedVersio

Tiger Daily: April 22, 2020

ANNOUNCEMENTS ZOOM Alert! COVID-19 Updates TILT Tip: Work with Your Library Liaison to Help Your Students! Calendar: Upcoming Professional Development Opportunities Tiger Food Pantry Academic Advising Training CANCELLED; Webinars Will Continue As Scheduled Accession Communicator Student Emergency Assistance Fund Together, Hays – FREE Mental/Physical Health Zoom Series TILT Resources, Tips, and Support Call for Nominations for the John Heinrichs Outstanding Undergraduate Research Mentor Award Adopt A Grandparent Online Resources for Those Struggling With Addictions Attention University Support Staff and Unclassified Professional Staff Zoom, Teams, Outlook, Accession, and CommPortal Training Opportunities 15th Annual John Heinrichs Scholarly and Creative Activities Day (SACAD)! EVENTS THIS WEEK/WEEKEND Earth Day – TODAY Earth Day – TODAY; 1:30pm to 3:30pm Lunch ‘N’ Learn – Cybersecurity Awareness: Protecting Data Regardless of Where You Are Working From – TOMORROW; 11:30am to 12:30pm FUTURE EVENTS Leveraging Strengths in Times of Crisis – April 28; 9:00am to 9:30am Virtual Times Talk: Dr. Anthony Fauci and How to Survive a Plague – April 28; 12:30pm to 1:30pm Denim Day – April 29 Time Management: Working from Home – April 30; 9:00am to 9:30am Coping & In Control: Caring for Yourself and Others – April 30; 11:30am to 12:30pm Where to Volunteer? – April 30; 2:00pm to 3:00pm Introduction to Pivot Tables – May 6; 9:00am to 9:30am World Red Cross Day – May 8; 1:30pm to 3:30pm Gain Control of Your Workday: Managing Self, Priorities, and Time – May 13; 9:00am to 12:00pm SHARE WITH STUDENTS New Fall 2020 Course: Write with Confidence! Complete Count 2020 Student Engagement Office Hours New Class Offers FHSU Students Opportunity to Try Out the Military Experience Recipe for Success: Art 36

Rapid high throughput SYBR green assay for identifying the malaria vectors Anophelese arabiensis, Anopheles coluzzii and Anopheles gambia s.s. Giles

The Anopheles gambiae sensu lato species complex consists of a number of cryptic species with different habitats and behaviours. These morphologically indistinct species are identified by chromosome banding. Several molecular diagnostic techniques for distinguishing between An. coluzzii and An. gambiae are still under improvement. Although, the current SINE method for identification between An. coluzzii and An. gambiae works reliably, this study describes a refinement of the SINE method to increase sensitivity for identification of An. coluzzii, An. gambiae and An. arabiensis based on amplicon dissociation curve characteristics. Field-collected samples, laboratory-reared colonies and crossed specimens of the two species were used for the design of the protocol. An. gambiae, An. coluzzii, and hybrids of the two species were sampled from Ghana and An. arabiensis from Kenya. Samples were first characterised using conventional SINE PCR method, and further assayed using SYBR green, an intercalating fluorescent dye. The three species and hybrids were clearly differentiated using the melting temperature of the dissociation curves, with derivative peaks at 72˚C for An. arabiensis, 75˚C for An. gambiae and 86˚C for An. coluzzii. The hybrids (An. gambiae / An. coluzzii) showed both peaks. This work is the first to describe a SYBR green real time PCR method for the characterization of An. arabiensis, An. gambiae and An. coluzzii and was purposely designed for basic melt-curve analysis (rather than high-resolution melt-curve) to allow it to be used on a wide range of real-time PCR machines

Potential of Genome Editing to Improve Aquaculture Breeding and Production

Aquaculture is an increasingly important component of global food security, and there is major potential for genetic improvement to contribute to sustainable production. The high fecundity and external fertilisation of most aquaculture species are amenable to the application of genetic improvement technologies, including genome editing using CRISPR/Cas9. Disease resistance is a major target trait for improvement, and CRISPR/Cas9 offers new opportunities to fix existing alleles, to perform introgression-by-editing of alleles from wild populations or related species, and to create de novo alleles. Combining in vivo and in vitro screening approaches has the potential to identify functional disease resistance alleles for downstream functional testing and application. Using genome editing to achieve 100% sterility of production animals is a promising avenue to prevent interbreeding of escapees with wild stocks

Effect of Different Inducer Sources on Cellulase Enzyme Production by White-Rot Basidiomycetes Pleurotus ostreatus and Phanerochaete chrysosporium under Submerged Fermentation

Cellulase enzymes attract a lot of research due to their industrial application. Diverse cellulase-producing organisms and substances that induce cellulase are highly sought after. This study aimed to evaluate the effect of different inducer sources on cellulase production by white rot fungi P. ostreatus CGMCC 3.7292 and P. chrysosporium CGMCC 3.7212 under submerged fermentation employing a completely randomized experimental design. The different inducer sources tested were nitrogen (yeast, potassium nitrate, sodium nitrate, ammonium sulphate, aqueous ammonia and urea), carbon (malt extract, glucose, fructose, carboxymethylcellulose, starch and xylose) and agro-biomass (stevia straw, wheat straw, oat straw, alfalfa straw, corn cobs and corn stover). These inducer sources strongly impacted enzyme activities by P. ostreatus CGMCC 3.7292 and P. chrysosporium CGMCC 3.7212. The suitable nitrogen and carbon inducer sources for cellulase activity by P. ostreatus and P. chrysosporium were yeast (1.354 U/mL and 1.154 U/mL) and carboxymethylcellulose (0.976 U/mL and 0.776 U/mL) while the suitable agro-biomass were wheat straw (6.880 U/mL) and corn stover (6.525 U/mL), respectively. The least inducer sources in terms of nitrogen, carbon and agro-biomass for cellulase activity by P. ostreatus and P. chrysosporium were urea (0.213 U/mL and 0.081 U/mL), glucose (0.042 U/mL and 0.035), xylose (0.042 U/mL and 0.035 U/mL) and stevia straw (1.555 U/mL and 0.960 U/mL). In submerged fermentation, the cellulase enzyme activity of P. ostreatus in response to various inducer sources was relatively higher than P. chrysosporium

Okra pectin as lecithin substitute in chocolate

The effect of okra (Abelmoschus spp.) pectin as an emulsifier on the yield, textural properties, sensory and consumer acceptability of different chocolate formulations was investigated. Pectin was isolated from okra pods and incorporated into milk chocolate as lecithin substitute (emulsifier) at different levels (10–100%). Texture profile analysis and sensory evaluation (5-point hedonic scale) was performed on the different chocolate formulations. It was found that with increasing pectin content viscosity of the mixed system increased during milling and conching, which resulted in slower flow rate during draining from the ball mill and decreased yield. Substitution at 25:0 (%) (pectin: lecithin) yielded 84 bars of 9 g of chocolate per 1500 g of formulation after draining for 30 min compared to formulations containing lecithin. Chocolate samples 25:75 (%) (pectin:lecithin) had the highest overall acceptability (4.37 ± 0.30) which was not significantly different (p> 0.05) from sample 25:0 with overall acceptability of 4.23 ± 0.30. All the chocolate samples from the various formulations studied had similar sensory properties as well as textural parameters (hardness, cohesiveness, adhesiveness, springiness and chewiness). The present findings suggest that it is possible to use okra pectin as emulsifier to produce milk chocolate which is acceptable to consumers. Keywords: Okra pectin, Chocolate, Emulsifier, Texture profile, Sensory propertie