Preferred carbon precursors for lipid labelling in the heterotrophic endosperm of developing oat (Avena sativa L.) grains

Grimberg, Åsa

doi:10.1016/j.plaphy.2014.08.018

Cited by 7 publications

(4 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, with respect to the 13 C-labeled substrates, we cannot distinguish if the organic acids taken up via the xylem stream were fully used for biosynthesis or if they partly accumulated in the leaves. Δ Label values in lipids for both species suggested that only small amounts of the position-specific 13 C-labeled malate and pyruvate were used for lipogenesis ( Figures 3 and 4 ); similar results was found in a recent 14 C labeling study ( Grimberg, 2014 ). Low Δ Label values in sugars in H. halimifolium might be explained by photosynthetic fixation of respired CO 2 derived from the 13 C-labeled substrates, as previously observed for pyruvate ( Tcherkez et al, 2005 ) or malate substrates ( Hibberd and Quick, 2002 ).…”

Section: Discussionsupporting

confidence: 85%

Metabolic Fate of the Carboxyl Groups of Malate and Pyruvate and their Influence on δ13C of Leaf-Respired CO2 during Light Enhanced Dark Respiration

et al. 2016

View full text Add to dashboard Cite

The enhanced CO2 release of illuminated leaves transferred into darkness, termed “light enhanced dark respiration (LEDR)”, is often associated with an increase in the carbon isotope ratio of the respired CO2 (δ13CLEDR). The latter has been hypothesized to result from different respiratory substrates and decarboxylation reactions in various metabolic pathways, which are poorly understood so far. To provide a better insight into the underlying metabolic processes of δ13CLEDR, we fed position-specific 13C-labeled malate and pyruvate via the xylem stream to leaves of species with high and low δ13CLEDR values (Halimium halimifolium and Oxalis triangularis, respectively). During respective label application, we determined label-derived leaf 13CO2 respiration using laser spectroscopy and the 13C allocation to metabolic fractions during light–dark transitions. Our results clearly show that both carboxyl groups (C-1 and C-4 position) of malate similarly influence respiration and metabolic fractions in both species, indicating possible isotope randomization of the carboxyl groups of malate by the fumarase reaction. While C-2 position of pyruvate was only weakly respired, the species-specific difference in natural δ13CLEDR patterns were best reflected by the 13CO2 respiration patterns of the C-1 position of pyruvate. Furthermore, 13C label from malate and pyruvate were mainly allocated to amino and organic acid fractions in both species and only little to sugar and lipid fractions. In summary, our results suggest that respiration of both carboxyl groups of malate (via fumarase) by tricarboxylic acid cycle reactions or by NAD-malic enzyme influences δ13CLEDR. The latter supplies the pyruvate dehydrogenase reaction, which in turn determines natural δ13CLEDR pattern by releasing the C-1 position of pyruvate.

show abstract

Section: Discussionsupporting

confidence: 85%

Metabolic Fate of the Carboxyl Groups of Malate and Pyruvate and their Influence on δ13C of Leaf-Respired CO2 during Light Enhanced Dark Respiration

et al. 2016

View full text Add to dashboard Cite

show abstract

“…To better understand how carbon allocation was affected by expression of AsWRI1, 14 C pulse-chase labelling of seeds developing on detached spikes was performed using a similar in vitro system to those previously used to study oat and wheat [32][33][34]. The net accumulated 14 C from fed sucrose in the endosperm of grains was approximately the same, about 50000 dpm/grain for the multiple insert line and the control (Fig.…”

Section: Pulse-chased 14 C-sucrose Shows Drastic Changes In Carbon Allocationmentioning

confidence: 99%

“…Six grains were sampled from mid part of spikes directly after the given pulse (0 h) and up to 192 h. Grains were frozen in N 2 (l) before cutting off embryo to harvest endosperms into plastic tubes further snap frozen in N 2 (l) and saved in − 80°C. Determination of 14 C-label in different endosperm fractions was done as described previously [33] except that heptane:diethylether:acetic acid (70:30:1 volume) was used during separation of lipid classes.…”

Section: Pulse-chase Experimentsmentioning

confidence: 99%

Transitions in wheat endosperm metabolism upon transcriptional induction of oil accumulation by oat endosperm WRINKLED1

et al. 2020

Self Cite

View full text Add to dashboard Cite

Background: Cereal grains, including wheat (Triticum aestivum L.), are major sources of food and feed, with wheat being dominant in temperate zones. These end uses exploit the storage reserves in the starchy endosperm of the grain, with starch being the major storage component in most cereal species. However, oats (Avena sativa L.) differs in that the starchy endosperm stores significant amounts of oil. Understanding the control of carbon allocation between groups of storage compounds, such as starch and oil, is therefore important for understanding the composition and hence end use quality of cereals. WRINKLED1 is a transcription factor known to induce triacylglycerol (TAG; oil) accumulation in several plant storage tissues. Results: An oat endosperm homolog of WRI1 (AsWRI1) expressed from the endosperm-specific HMW1Dx5 promoter resulted in drastic changes in carbon allocation in wheat grains, with reduced seed weight and a wrinkled seed phenotype. The starch content of mature grain endosperms of AsWRI1-wheat was reduced compared to controls (from 62 to 22% by dry weight (dw)), TAG was increased by up to nine-fold (from 0.7 to 6.4% oil by dw) and sucrose from 1.5 to 10% by dw. Expression of AsWRI1 in wheat grains also resulted in multiple layers of elongated peripheral aleurone cells. RNA-sequencing, lipid analyses, and pulse-chase experiments using 14 C-sucrose indicated that futile cycling of fatty acids could be a limitation for oil accumulation.Conclusions: Our data show that expression of oat endosperm WRI1 in the wheat endosperm results in changes in metabolism which could underpin the application of biotechnology to manipulate grain composition. In particular, the striking effect on starch synthesis in the wheat endosperm indicates that an important indirect role of WRI1 is to divert carbon allocation away from starch biosynthesis in plant storage tissues that accumulate oil.

show abstract

“…The most common use of A.S is livestock feeding. Primary cereal crops such as wheat and barley are usually considered secondary crops, as they are derived from undesirable weeds [1,2].…”

mentioning

confidence: 99%

Review Article on the Plant Avena Sativa Linn.

2023

IJBPAS

View full text Add to dashboard Cite

Avena Sativa, sometimes known as oat, is a plant that belongs to the Poaceae family. Third in importance after wheat and corn in the United States, and fourth in importance worldwide. As far as nutrition is concerned, they are one of the most widely produced plants. Moreover, it is commercially nutritious. Soluble dietary fibre can be found in oat grain, oat bran, and oatmeal known as -glucan, which can lower total cholesterol and low-density lipoprotein cholesterol levels in the blood. Lipoprotein cholesterol is also useful for controlling blood sugar levels.Experiments of many kinds Oat has been proven in tests to be a possible agent for preventing the onset and progression of cancer , intestinal malfunction, obesity, celiac disease, and other disorders This examination will Avena Sativa's therapeutic and utilitarian characteristics are discussed. The functional and therapeutic aspects of Avena Sativa will be discussed in this review. However, due to the large number of the health benefits they provide, their intake has raised significantly, and they have become more popular come to the foreground immediately.

show abstract

Preferred carbon precursors for lipid labelling in the heterotrophic endosperm of developing oat (Avena sativa L.) grains

Cited by 7 publications

References 56 publications

Metabolic Fate of the Carboxyl Groups of Malate and Pyruvate and their Influence on δ13C of Leaf-Respired CO2 during Light Enhanced Dark Respiration

Metabolic Fate of the Carboxyl Groups of Malate and Pyruvate and their Influence on δ13C of Leaf-Respired CO2 during Light Enhanced Dark Respiration

Transitions in wheat endosperm metabolism upon transcriptional induction of oil accumulation by oat endosperm WRINKLED1

Review Article on the Plant Avena Sativa Linn.

Contact Info

Product

Resources

About