Allopolyploidy expanded gene content but not pangenomic variation in the hexaploid oilseed Camelina sativa.

Ancient whole-genome duplications (WGDs) are believed to facilitate novelty and adaptation by providing the raw fuel for new genes. However, it is unclear how recent WGDs may contribute to evolvability within recent polyploids. Hybridization accompanying some WGDs may combine divergent gene content among diploid species.

Targeted engineering of camelina and pennycress seeds for ultrahigh accumulation of acetyl-TAG.

Acetyl-TAG (3-acetyl-1,2-diacylglycerol), unique triacylglycerols (TAG) possessing an acetate group at the -3 position, exhibit valuable properties, such as reduced viscosity and freezing points. Previous attempts to engineer acetyl-TAG production in oilseed crops did not achieve the high levels found in naturally producing seeds. Here, we demonstrate the successful generation of camelina and pennycress transgenic lines accumulating nearly pure acetyl-TAG at 93 mol% and 98 mol%, respectively.

Creating yellow seed Camelina sativa with enhanced oil accumulation by CRISPR-mediated disruption of Transparent Testa 8.

Camelina (Camelina sativa L.), a hexaploid member of the Brassicaceae family, is an emerging oilseed crop being developed to meet the increasing demand for plant oils as biofuel feedstocks. In other Brassicas, high oil content can be associated with a yellow seed phenotype, which is unknown for camelina.

Heat stress during reproductive stages reduces camelina seed productivity and changes seed composition.

Camelina ( L. Crantz) is a low-input oilseed crop with great potential in bioenergy and industrial oils. Improving tolerance to high temperatures is essential for camelina agronomic sustainability.

Interaction between phenylpropane metabolism and oil accumulation in the developing seed of Brassica napus revealed by high temporal-resolution transcriptomes.

Background: Brassica napus is an important oilseed crop providing high-quality vegetable oils for human consumption and non-food applications. However, the regulation between embryo and seed coat for the synthesis of oil and phenylpropanoid compounds remains largely unclear.

Results: Here, we analyzed the transcriptomes in developing seeds at 2-day intervals from 14 days after flowering (DAF) to 64 DAF.

Oil plant genomes: current state of the science.

Vegetable oils are an indispensable nutritional component of the human diet as well as important raw materials for a variety of industrial applications such as pharmaceuticals, cosmetics, oleochemicals, and biofuels. Oil plant genomes are highly diverse, and their genetic variation leads to a diversity in oil biosynthesis and accumulation along with agronomic traits. This review discusses plant oil biosynthetic pathways, current state of genome assembly, polyploidy and asymmetric evolution of genomes of oil plants and their wild relatives, and research progress of pan-genomics in oil plants.

Genetic dissection of natural variation in oilseed traits of camelina by whole-genome resequencing and QTL mapping.

Camelina [Camelina sativa (L.) Crantz] is an oilseed crop in the Brassicaceae family that is currently being developed as a source of bioenergy and healthy fatty acids. To facilitate modern breeding efforts through marker-assisted selection and biotechnology, we evaluated genetic variation among a worldwide collection of 222 camelina accessions.

Mapping quantitative trait loci for seed traits in Camelina sativa.

Genetic dissection of oil content and seed size in Camelina sativa was conducted by QTL mapping using a SNP-based linkage map and a recombinant inbred population. Camelina (Camelina sativa L. Crantz) is an oilseed crop that has great potential to provide sustainable feedstock for biofuel production and to improve dryland agriculture.

Enhancing microRNA167A expression in seed decreases the α-linolenic acid content and increases seed size in Camelina sativa.

Despite well established roles of microRNAs in plant development, few aspects have been addressed to understand their effects in seeds especially on lipid metabolism. In this study, we showed that overexpressing microRNA167A (miR167OE) in camelina (Camelina sativa) under a seed-specific promoter changed fatty acid composition and increased seed size. Specifically, the miR167OE seeds had a lower α-linolenic acid with a concomitantly higher linoleic acid content than the wild-type.

Seed-specific suppression of ADP-glucose pyrophosphorylase in increases seed size and weight.

Background: Camelina ( L.) is a promising oilseed crop that may provide sustainable feedstock for biofuel production. One of the major drawbacks of Camelina is its smaller seeds compared to other major oil crops such as canola, which limit oil yield and may also pose challenges in successful seedling establishment, especially in dryland cultivation.

A Phospholipase C-Like Protein From Increases Hydroxy Fatty Acids Accumulation in Transgenic Seeds of .

There have been strong interests in producing unusual fatty acids in oilseed crops to provide renewable industrial feedstock. Results are so far largely disappointing since much lower amounts of such fatty acids accumulate in genetically engineered seeds than in their original natural sources. It has been suggested that the flux of unusual fatty acids through phosphatidylcholine (PC) represents a major bottleneck for high accumulation of such fatty acids in triacylglycerol (TAG).

Towards the synthetic design of camelina oil enriched in tailored acetyl-triacylglycerols with medium-chain fatty acids.

The ability to manipulate expression of key biosynthetic enzymes has allowed the development of genetically modified plants that synthesise unusual lipids that are useful for biofuel and industrial applications. By taking advantage of the unique activities of enzymes from different species, tailored lipids with a targeted structure can be conceived. In this study we demonstrate the successful implementation of such an approach by metabolically engineering the oilseed crop Camelina sativa to produce 3-acetyl-1,2-diacyl-sn-glycerols (acetyl-TAGs) with medium-chain fatty acids (MCFAs).

Improved fatty acid profiles in seeds of Camelina sativa by artificial microRNA mediated FATB gene suppression.

The fatty acid profile of plant oils determines their quality and uses. Saturated fatty acids are often not desirable from the standpoints of nutrition and some industrial applications. Camelina sativa is a re-emerged oilseed crop, however its oil needs to be improved to meet different application requirements.

Mutagenesis of the FAE1 genes significantly changes fatty acid composition in seeds of Camelina sativa.

Camelina sativa is a re-emerging low-input oilseed crop that has great potentials. It is necessary to ameliorate camelina oils for optimized fatty acid composition that can meet different application requirements. Camelina seed contains significant amounts of C20-C24 very long-chain fatty acids (VLCFAs) that may not be desirable.

Identification of multiple lipid genes with modifications in expression and sequence associated with the evolution of hydroxy fatty acid accumulation in Physaria fendleri.

Two Brassicaceae species, Physaria fendleri and Camelina sativa, are genetically very closely related to each other and to Arabidopsis thaliana. Physaria fendleri seeds contain over 50% hydroxy fatty acids (HFAs), while Camelina sativa and Arabidopsis do not accumulate HFAs. To better understand how plants evolved new biochemical pathways with the capacity to accumulate high levels of unusual fatty acids, transcript expression and protein sequences of developing seeds of Physaria fendleri, wild-type Camelina sativa, and Camelina sativa expressing a castor bean (Ricinus communis) hydroxylase were analyzed.

Identification of microRNAs and transcript targets in Camelina sativa by deep sequencing and computational methods.

Camelina sativa is an annual oilseed crop that is under intensive development for renewable resources of biofuels and industrial oils. MicroRNAs, or miRNAs, are endogenously encoded small RNAs that play key roles in diverse plant biological processes. Here, we conducted deep sequencing on small RNA libraries prepared from camelina leaves, flower buds and two stages of developing seeds corresponding to initial and peak storage products accumulation.

A fatty acid condensing enzyme from Physaria fendleri increases hydroxy fatty acid accumulation in transgenic oilseeds of Camelina sativa.

Co-expression of a lesquerella fatty acid elongase and the castor fatty acid hydroxylase in camelina results in higher hydroxy fatty acid containing seeds with normal oil content and viability. Producing hydroxy fatty acids (HFA) in oilseed crops has been a long-standing goal to replace castor oil as a renewable source for numerous industrial applications. A fatty acid hydroxylase, RcFAH, from Ricinus communis, was introduced into Camelina sativa, but yielded only 15 % of HFA in its seed oil, much lower than the 90 % found in castor bean.

Camelina seed transcriptome: a tool for meal and oil improvement and translational research.

Camelina (Camelina sativa), a Brassicaceae oilseed, has received recent interest as a biofuel crop and production platform for industrial oils. Limiting wider production of camelina for these uses is the need to improve the quality and content of the seed protein-rich meal and oil, which is enriched in oxidatively unstable polyunsaturated fatty acids that are deleterious for biodiesel. To identify candidate genes for meal and oil quality improvement, a transcriptome reference was built from 2047 Sanger ESTs and more than 2 million 454-derived sequence reads, representing genes expressed in developing camelina seeds.

Acyl editing and headgroup exchange are the major mechanisms that direct polyunsaturated fatty acid flux into triacylglycerols.

Triacylglycerols (TAG) in seeds of Arabidopsis (Arabidopsis thaliana) and many plant species contain large amounts of polyunsaturated fatty acids (PUFA). These PUFA are synthesized on the membrane lipid phosphatidylcholine (PC). However, the exact mechanisms of how fatty acids enter PC and how they are removed from PC after being modified to participate in the TAG assembly are unclear, nor are the identities of the key enzymes/genes that control these fluxes known.

The phosphatidylcholine diacylglycerol cholinephosphotransferase is required for efficient hydroxy fatty acid accumulation in transgenic Arabidopsis.

We previously identified an enzyme, phosphatidylcholine diacylglycerol cholinephosphotransferase (PDCT), that plays an important role in directing fatty acyl fluxes during triacylglycerol (TAG) biosynthesis. The PDCT mediates a symmetrical interconversion between phosphatidylcholine (PC) and diacylglycerol (DAG), thus enriching PC-modified fatty acids in the DAG pool prior to forming TAG. We show here that PDCT is required for the efficient metabolism of engineered hydroxy fatty acids in Arabidopsis (Arabidopsis thaliana) seeds.

Construction of a full-length cDNA library from castor endosperm for high-throughput functional screening.

It is desirable to produce high homogeneity of novel fatty acids in oilseeds through genetic engineering to meet increasing demands by the oleo-chemical industry. However, expression of key enzymes for biosynthesis of industrial fatty acids usually results in low levels of desired fatty acids in transgenic oilseeds. The abundance of unusual fatty acids in their natural species suggests that additional genes are needed for high production in transgenic plants.

Identification of three genes encoding microsomal oleate desaturases (FAD2) from the oilseed crop Camelina sativa.

Camelina sativa is a re-emerging low-input oilseed crop that may provide economical vegetable oils for industrial applications. It is desirable to increase the monounsaturated oleic acid (cis-9-octadecenoic acid, 18:1), and to decrease polyunsaturated fatty acids (PUFA), linoleic (cis, cis-9,12-octadecadienoic acid, 18:2) and α-linolenic (all-cis-9,12,15-octadecatrienoic acid, 18:3) acids, in camelina oils to improve oxidative stability. 18:1 desaturation is mainly controlled by the microsomal oleate desaturase (FAD2; EC 1.

New frontiers in oilseed biotechnology: meeting the global demand for vegetable oils for food, feed, biofuel, and industrial applications.

Vegetable oils have historically been a valued commodity for food use and to a lesser extent for non-edible applications such as detergents and lubricants. The increasing reliance on biodiesel as a transportation fuel has contributed to rising demand and higher prices for vegetable oils. Biotechnology offers a number of solutions to meet the growing need for affordable vegetable oils and vegetable oils with improved fatty acid compositions for food and industrial uses.