Influence Of Dietry Hufa Levels On Egg Production, Tissue Fatty Acid Profile And Desaturase And Elongase Mrnas Expression In Female Zebrafish (Danio Rerio).

Kajian ini telah dijalankan untuk meninjau kesan paras asid lemak sangat tidak tepu (HUFA) ke atas profil asid lemak dalam tisu dan prestasi pembiakan ikan zebrafish betina. This study was conducted to investigate the effect of varying levels of dietary highly unsaturated fatty acids (HUFA) on tissue fatty acid profiles and reproductive performance in female zebrafish

Functional Characterization Of The Striped Snakehead (Channa Striata) Desaturase Gene, And Its Implication In Long-Chain Polyunsaturated Fatty Acid Synthesis

Ikan merupakan sumber utama asid lemak rantai panjang poli-tak-tepu (LC-PUFA) omega-3, antaranya asid eikosapentaenoik (EPA) dan asid dokosaheksaenoic (DHA), yang penting bagi kesihatan optimum manusia. Fish are a major source of beneficial omega-3 long-chain polyunsaturated fatty acids (LC-PUFA) for optimal human health, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)

Upregulated mRNA expression of desaturase and elongase, two enzymes involved in highly unsaturated fatty acids biosynthesis pathways during follicle maturation in zebrafish

<p>Abstract</p> <p>Background</p> <p>Although unsaturated fatty acids such as eicosapentaenoic acid (EPA, C20:5n-3), docosahexaenoic acid (DHA, C22:6n-3) and arachidonic acid (ARA, C20:4n-6), collectively known as the highly unsaturated fatty acids (HUFA), play pivotal roles in vertebrate reproduction, very little is known about their synthesis in the ovary. The zebrafish (Danio rerio) display capability to synthesize all three HUFA via pathways involving desaturation and elongation of two precursors, the linoleic acid (LA, C18:2n-6) and linolenic acid (LNA, C18:3n-3). As a prerequisite to gain full understanding on the importance and regulation of ovarian HUFA synthesis, we described here the mRNA expression pattern of two enzymes; desaturase (fadsd6) and elongase (elovl5), involved in HUFA biosynthesis pathway, in different zebrafish ovarian follicle stages. Concurrently, the fatty acid profile of each follicle stage was also analyzed.</p> <p>Methods</p> <p>mRNA levels of fadsd6 and elovl5 in different ovarian follicle stages were determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) assays. For analysis of the ovarian follicular fatty acid composition, gas chromatography was used.</p> <p>Results</p> <p>Our results have shown that desaturase displayed significant upregulation in expression during the oocyte maturation stage. Expression of elongase was significantly highest in pre-vitellogenic follicles, followed by maturation stage. Fatty acid composition analysis of different ovarian follicle stages also showed that ARA level was significantly highest in pre-vitellogenic and matured follicles. DHA level was highest in both late vitellogenic and maturation stage.</p> <p>Conclusion</p> <p>Collectively, our findings seem to suggest the existence of a HUFA synthesis system, which could be responsible for the synthesis of HUFA to promote oocyte maturation and possibly ovulation processes. The many advantages of zebrafish as model system to understand folliculogenesis will be useful platform to further elucidate the regulatory and mechanism aspects of ovarian HUFA synthesis.</p

Long-chain polyunsaturated fatty acid biosynthesis in a land-crab with advanced terrestrial adaptations: Molecular cloning and functional characterization of two fatty acyl elongases

Depending on the presence and activities of the front-end fatty acyl desaturases and elongation of very long-chain fatty acid (Elovl) enzymes, animals have different capacities for long-chain (≥C20) polyunsaturated fatty acids (LC-PUFA) biosynthesis. Successful land colonisation in brachyuran crabs requires a shift towards terrestrial food chain with limited LC-PUFA availability. We cloned and functionally characterised two elovl genes from the purple land crab Gecarcoidea lalandii. The two Elovl contained all the necessary motifs of a typical polyunsaturated fatty acids (PUFA) Elovl and phylogenetically clustered in the Elovl1 and Elovl6 clades, respectively. The G. lalandii Elovl1 elongated saturated fatty acids, with low activities towards C20 and C22 PUFA substrates. Moreover, the G. lalandii Elovl6 was particularly active in the elongation of C18 PUFA, although it also recognised monounsaturated fatty acids as substrates for elongation. Collectively, the herein characterised G. lalandii elovl paralogues fulfil all the elongation steps involved in the LC-PUFA biosynthetic pathways. Tissue distribution of the G. lalandii elovl genes, along with the FA composition analyses, suggest the hepatopancreas and gill as key metabolic sites for fatty acid elongation. However, current data suggest that G. lalandii is unable to rely solely on biosynthesis to fulfil LC-PUFA requirements, since front-end desaturase appears to be absent in this species and other decapods.We are grateful to the Ministry of Higher Education Malaysia for Fundamental Research Grant Scheme with Project Code: FRGS/1/2018/STG05/USM/01/4. Moreover, this study was partly funded through the project IMPROMEGA of the Ministry of Science, Innovation and Universities, Spanish Government (RTI2018-095119-B-100, MCIU/AEI/FEDER/UE). We also thank Universiti Sains Malaysia for the appointment of Óscar Monroig as Adjunct Academic Fellow USM. 9/1/v Jld. XIII)

Impact of the citizen science project COLLECT on ocean literacy and well-being within a north/west African and south-east Asian context

Plastic pollution is both a societal and environmental problem and citizen science has shown to be a useful tool to engage both the public and professionals in addressing it. However, knowledge on the educational and behavioral impacts of citizen science projects focusing on marine litter remains limited. Our preregistered study investigates the impact of the citizen science project Citizen Observation of Local Litter in coastal ECosysTems (COLLECT) on the participants' ocean literacy, pro-environmental intentions and attitudes, well-being, and nature connectedness, using a pretest-posttest design. A total of 410 secondary school students from seven countries, in Africa (Benin, Cabo Verde, Cote d'Ivoire, Ghana, Morocco, Nigeria) and Asia (Malaysia) were trained to sample plastics on sandy beaches and to analyze their collection in the classroom. Non-parametric statistical tests (n = 239 matched participants) demonstrate that the COLLECT project positively impacted ocean literacy (i.e., awareness and knowledge of marine litter, self-reported litter-reducing behaviors, attitudes towards beach litter removal). The COLLECT project also led to higher pro-environmental behavioral intentions for students in Benin and Ghana (implying a positive spillover effect) and higher well-being and nature connectedness for students in Benin. Results are interpreted in consideration of a high baseline in awareness and attitudes towards marine litter, a low internal consistency of pro-environmental attitudes, the cultural context of the participating countries, and the unique settings of the project's implementation. Our study highlights the benefits and challenges of understanding how citizen science impacts the perceptions and behaviors towards marine litter in youth from the respective regions.info:eu-repo/semantics/publishedVersio

The effects of tank colour, live food enrichment and greenwater on the early onset of jaw malformation in striped trumpeter larvae

A high incidence of jaw malformation has hindered the production of quality striped trumpeter Latris lineata juveniles and has been correlated with walling behaviour in Artemia-fed larvae. In this study, striped trumpeter were reared from first feeding to 29 days post-hatching (dph) in different coloured tanks (black or white), culture conditions (clear or greenwater) and fed different diets (enriched or non-enriched rotifers and Artemia), to examine behaviour, retinoid receptor gene expression and jaw malformation. The highest incidence and severity of jaw malformations occurred in clearwater and enriched diet treatments and were significantly more common in white (70 +/- 15%, mean +/- SD) than in black tanks (26 +/- 15%). In black tanks, jaw malformation was significantly more common in larvae fed enriched diets (18 +/- 14%) than in those fed non-enriched diets (8 +/- 8%) and in clearwater (19 +/- 14%) versus greenwater (7 +/- 6%). At the end of the rotifer feeding phase, larvae were significantly larger in black than white tanks, and longer in greenwater than in clearwater. In the Artemia feeding phase, larval growth was slowest and mortality was highest in non-enriched diet treatments. Larval length and survival were higher in black tanks and in enriched diet treatments, whilst survival was almost twice as high in greenwater (46 +/- 18%) than clearwater (26 +/- 13%). The average proportion of larvae walling over the duration of the experiment was higher in white than black tanks, and higher in enriched than non-enriched treatments, with lowest walling in greenwater. There was no consistent relationship between feed intake and jaw malformation. However, there was a significant positive correlation between walling and the incidence of jaw malformation at 29 dph in larvae fed enriched diets. The expression pattern of three retinoid receptor genes indicated that live feed enrichment and stress could potentially perturb retinoic acid-associated pathways leading to skeletal abnormality. We found that the use of greenwater, black tanks and enriched live feeds is required for good growth, development, survival and final yield of striped trumpeter. The study emphasises the importance of reducing walling in the culture of oceanic larvae and may have direct application in the rearing of other marine fish with similar malformations

Addressing data gaps in marine litter distribution : citizen science observation of plastics in coastal ecosystems by high-school students

The Citizen Observation of Local Litter in coastal ECosysTems (COLLECT) project (2021-2022) is a citizen science initiative, supported by the Partnership for Observation of the Global Ocean (POGO), which aimed to acquire distribution and abundance data of coastal plastic litter in seven countries: in Africa (Benin, Cabo Verde, Cote d'Ivoire, Ghana, Morocco, Nigeria) and Asia (Malaysia). In this paper, we describe the workflow used to establish and run this project, as well as the methodologies to acquire data. The COLLECT project consisted of training local students (15 - 18 years old) from ten second cycle institutions ( "high schools ") on sampling and analyzing macro-, meso- and microplastics in beach sediments, using a quantitative assessment protocol. We further describe in detail the methodologies applied in assessing the impact of participating in the activities from a social sciences perspective. All documents and materials resulting from this project will be open access and available according to the FAIR Principles (Findable, Accessible, Interoperable, and Reusable). The results and outcomes from COLLECT will contribute to expanding knowledge and establishing baseline information on coastal plastic pollution, with citizen science being an enabler of open science, allowing data to be freely available to the public, academics and policymakers. Expected results from the use of the COLLECT protocol globally will further contribute to the identification of hotspots of coastal plastic litter, and bring awareness to local communities on the potential consequences of plastic pollution. The COLLECT project actively contributes with data suitable to survey plastic litter to the United Nations' Sustainable Development Goals (UN SDGs), in particular to SDG 14, on the sustainable use of the ocean