Click
here to close Hello! We notice that
you are using Internet Explorer, which is not supported by Echinobase
and may cause the site to display incorrectly. We suggest using a
current version of Chrome,
FireFox,
or Safari.
PLoS One
2017 Jan 01;121:e0169374. doi: 10.1371/journal.pone.0169374.
Show Gene links
Show Anatomy links
Biosynthesis of Polyunsaturated Fatty Acids in Sea Urchins: Molecular and Functional Characterisation of Three Fatty Acyl Desaturases from Paracentrotus lividus (Lamark 1816).
Kabeya N
,
Sanz-Jorquera A
,
Carboni S
,
Davie A
,
Oboh A
,
Monroig O
.
Abstract
Sea urchins are broadly recognised as a delicacy and their quality as food for humans is highly influenced by their diet. Lipids in general and the long-chain polyunsaturated fatty acids (LC-PUFA) in particular, are essential nutrients that determine not only the nutritional value of sea urchins but also guarantee normal growth and reproduction in captivity. The contribution of endogenous production (biosynthesis) of LC-PUFA in sea urchins remained unknown. Using Paracentrotus lividus as our model species, we aimed to characterise both molecularly and functionally the repertoire of fatty acyl desaturases (Fads), key enzymes in the biosynthesis of LC-PUFA, in sea urchins. Three Fads, namely FadsA, FadsC1 and FadsC2, were characterised. The phylogenetic analyses suggested that the repertoire of Fads within the Echinodermata phylum varies among classes. On one hand, orthologues of the P. lividus FadsA were found in other echinoderm classes including starfishes, brittle stars and sea cucumbers, thus suggesting that this desaturase is virtually present in all echinoderms. Contrarily, the FadsC appears to be sea urchin-specific desaturase. Finally, a further desaturase termed as FadsB exists in starfishes, brittle stars and sea cucumbers, but appears to be missing in sea urchins. The functional characterisation of the P. lividus Fads confirmed that the FadsA was a Δ5 desaturase with activity towards saturated and polyunsaturated fatty acids (FA). Moreover, our experiments confirmed that FadsA plays a role in the biosynthesis of non-methylene interrupted FA, a group of compounds typically found in marine invertebrates. On the other hand, both FadsC desaturases from P. lividus showed Δ8 activity. The present results demonstrate that P. lividus possesses desaturases that account for all the desaturation reactions required to biosynthesis the physiological essential eicosapentaenoic and arachidonic acids through the so-called "Δ8 pathway".
Fig 1. Biosynthetic pathways of LC-PUFA from C18 PUFA precursors accepted in vertebrates.Reactions catalysed by fatty acyl desaturases are designated as âÎxâ (Î6, Î5, Î4 and Î8), whereas elongation reactions are indicated as âelongaseâ.
Fig 2. Comparison of the deduced amino acid sequence of the Paracentrotus lividus desaturases with those of mice (Mus musculus), zebrafish (Danio rerio) and common octopus (Octopus vulgaris).Identical sequences are shaded black. All the Fads sequence from P. lividus contained typically conserved regions in members of the front-end desaturase family, including three histidine boxes (HXXXH, HXXHH and QXXHH), a putative cytochrome b5-like region (marked as a dotted line) and a heme-binding motif (HPGG).
Fig 3. Phylogenetic tree comparing the deduced amino acid (aa) sequence of the Paracentrotus lividus fatty acyl desaturases (Fads) with other Fads-like sequences from different organisms (vertebrates and invertebrates).FadsA, FadsC1 and FadsC2 are highlighted in black. The tree was constructed using the Neighbour Joining method [38]. The horizontal branch length is proportional to aa substitution rate per site. The numbers represent the frequencies (%) with which the tree topology presented was replicated after 1,000 iterations. Asterisks denote deduced aa sequences derived from transcriptome shotgun assembly (TSA) from several echinoderm species.
Fig 4. Functional characterisation of FadsA from Paracentrotus lividus in transformed yeast Saccharomyces cerevisiae.Additional 18:1n-13 peak was observed in all the yeast transformed with pYES2-FadsA (BâF) compared with the yeast transformed with empty pYES2 vector (A). The yeast transformed with pYES2-FadsA were also grown in the presence of fatty acid (FA) substrates (indicated by asterisk), namely 20:3n-3 (C), 20:2n-6 (D), 20:4n-3 (E) and 20:3n-6 (F). Desaturation products are indicated accordingly in each panel. Peaks 1â4 in all panels are the main endogenous FA of S. cerevisiae, namely 16:0 (1), 16:1 isomers (2), 18:0 (3), 18:1n-9 (4). Vertical axis, FID response; horizontal axis, retention time.
Fig 5. Functional characterisation of FadsC1 and FadsC2 from Paracentrotus lividus in transformed yeast S. cerevisiae.The fatty acid (FA) profiles of yeast transformed with pYES2-FadsC1 (A, B) and pYES2-FadsC2 (C, D) were determined after they were grown in the presence of FA substrates (indicated by asterisk), namely 20:3n-3 (A, C) and 20:2n-6 (B, D). Moreover, desaturation products are indicated accordingly in each panel. Peaks 1â4 in all panels are the main endogenous FA of S. cerevisiae, namely 16:0 (1), 16:1 isomers (2), 18:0 (3), 18:1n-9 (4). Vertical axis, FID response; horizontal axis, retention time.
Awada,
n-3 PUFA added to high-fat diets affect differently adiposity and inflammation when carried by phospholipids or triacylglycerols in mice.
2013, Pubmed
Awada,
n-3 PUFA added to high-fat diets affect differently adiposity and inflammation when carried by phospholipids or triacylglycerols in mice.
2013,
Pubmed
Barnathan,
Non-methylene-interrupted fatty acids from marine invertebrates: Occurrence, characterization and biological properties.
2009,
Pubmed
Carboni,
Fatty acid profiles during gametogenesis in sea urchin (Paracentrotus lividus): effects of dietary inputs on gonad, egg and embryo profiles.
2013,
Pubmed
,
Echinobase
Castro,
Functional desaturase Fads1 (Δ5) and Fads2 (Δ6) orthologues evolved before the origin of jawed vertebrates.
2012,
Pubmed
Castro,
Long-chain polyunsaturated fatty acid biosynthesis in chordates: Insights into the evolution of Fads and Elovl gene repertoire.
2016,
Pubmed
Cook,
Fatty acid compositions of gonadal material and diets of the sea urchin, Psammechinus miliaris: trophic and nutritional implications.
2000,
Pubmed
,
Echinobase
FOLCH,
A simple method for the isolation and purification of total lipides from animal tissues.
1957,
Pubmed
Fonseca-Madrigal,
Diversification of substrate specificities in teleostei Fads2: characterization of Δ4 and Δ6Δ5 desaturases of Chirostoma estor.
2014,
Pubmed
Guillou,
The key roles of elongases and desaturases in mammalian fatty acid metabolism: Insights from transgenic mice.
2010,
Pubmed
Hastings,
A vertebrate fatty acid desaturase with Delta 5 and Delta 6 activities.
2001,
Pubmed
Hui,
Extensive chordate and annelid macrosynteny reveals ancestral homeobox gene organization.
2012,
Pubmed
Jakobsson,
Fatty acid elongases in mammals: their regulation and roles in metabolism.
2006,
Pubmed
Lee,
Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances.
2016,
Pubmed
Liu,
Functional characterization of a Δ5-like fatty acyl desaturase and its expression during early embryogenesis in the noble scallop Chlamys nobilis Reeve.
2014,
Pubmed
Liu,
PUFA biosynthesis pathway in marine scallop Chlamys nobilis Reeve.
2014,
Pubmed
Liyana-Pathirana,
Effect of season and artificial diet on amino acids and nucleic acids in gonads of green sea urchin Strongylocentrotus droebachiensis.
2002,
Pubmed
,
Echinobase
Meesapyodsuk,
The front-end desaturase: structure, function, evolution and biotechnological use.
2012,
Pubmed
Monroig,
Biosynthesis of polyunsaturated fatty acids in marine invertebrates: recent advances in molecular mechanisms.
2013,
Pubmed
Monroig,
Identification of a Δ5-like fatty acyl desaturase from the cephalopod Octopus vulgaris (Cuvier 1797) involved in the biosynthesis of essential fatty acids.
2012,
Pubmed
Montes,
Fatty-acid composition of maternal and umbilical cord plasma and early childhood atopic eczema in a Spanish cohort.
2013,
Pubmed
Muhlhausler,
Omega-6 polyunsaturated fatty acids and the early origins of obesity.
2013,
Pubmed
Raible,
Vertebrate-type intron-rich genes in the marine annelid Platynereis dumerilii.
2005,
Pubmed
Saitou,
The neighbor-joining method: a new method for reconstructing phylogenetic trees.
1987,
Pubmed
Sergiev,
Genomes of Strongylocentrotus franciscanus and Lytechinus variegatus: are there any genomic explanations for the two order of magnitude difference in the lifespan of sea urchins?
2016,
Pubmed
,
Echinobase
Siliani,
Influence of seasonal and environmental patterns on the lipid content and fatty acid profiles in gonads of the edible sea urchin Paracentrotus lividus from Sardinia.
2016,
Pubmed
,
Echinobase
Sodergren,
The genome of the sea urchin Strongylocentrotus purpuratus.
2006,
Pubmed
,
Echinobase
Sprague,
Replacement of fish oil with a DHA-rich algal meal derived from Schizochytrium sp. on the fatty acid and persistent organic pollutant levels in diets and flesh of Atlantic salmon (Salmo salar, L.) post-smolts.
2015,
Pubmed
Surm,
Comparative Analysis and Distribution of Omega-3 lcPUFA Biosynthesis Genes in Marine Molluscs.
2015,
Pubmed
Takahashi,
An EST screen from the annelid Pomatoceros lamarckii reveals patterns of gene loss and gain in animals.
2009,
Pubmed
van der Merwe,
Long-chain PUFA supplementation in rural African infants: a randomized controlled trial of effects on gut integrity, growth, and cognitive development.
2013,
Pubmed