Limits...
Lipidomic analysis of Arabidopsis seed genetically engineered to contain DHA.

Zhou XR, Callahan DL, Shrestha P, Liu Q, Petrie JR, Singh SP - Front Plant Sci (2014)

Bottom Line: Metabolic engineering of omega-3 long-chain (≥C20) polyunsaturated fatty acids (ω3 LC-PUFA) in oilseeds has been one of the key targets in recent years.Liquid chromatography-mass spectrometry (LC-MS) was used to characterize the triacylglycerol (TAG), diacylglycerol (DAG) and phospholipid (PL) lipid classes in the transgenic and wild type Arabidopsis seeds at both developing and mature stages.Trace amounts of di-DHA PC and tri-DHA TAG were identified and confirmed by high resolution MS/MS.

View Article: PubMed Central - PubMed

Affiliation: Food Futures National Research Flagship, Commonwealth Scientific and Industrial Research Organisation Canberra, ACT, Australia ; Plant Industry, Commonwealth Scientific and Industrial Research Organisation Canberra, ACT, Australia.

ABSTRACT
Metabolic engineering of omega-3 long-chain (≥C20) polyunsaturated fatty acids (ω3 LC-PUFA) in oilseeds has been one of the key targets in recent years. By expressing a transgenic pathway for enhancing the synthesis of the ω3 LC-PUFA docosahexaenoic acid (DHA) from endogenous α-linolenic acid (ALA), we obtained the production of fish oil-like proportions of DHA in Arabidopsis seed oil. Liquid chromatography-mass spectrometry (LC-MS) was used to characterize the triacylglycerol (TAG), diacylglycerol (DAG) and phospholipid (PL) lipid classes in the transgenic and wild type Arabidopsis seeds at both developing and mature stages. The analysis identified the appearance of several abundant DHA-containing phosphatidylcholine (PC), DAG and TAG molecular species in mature seeds. The relative abundances of PL, DAG, and TAG species showed a preferred combination of LC-PUFA with ALA in the transgenic seeds, where LC-PUFA were esterified in positions usually occupied by 20:1ω9. Trace amounts of di-DHA PC and tri-DHA TAG were identified and confirmed by high resolution MS/MS. Studying the lipidome in transgenic seeds provided insights into where DHA accumulated and combined with other fatty acids of neutral and phospholipids from the developing and mature seeds.

No MeSH data available.


Total phospholipids in developing and mature Arabidopsis seeds. Phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylinositol (PI) and phosphatidylserine (PS) were determined from triplicate samples with the mean and standard deviation shown. WT-m, Columbia wild type mature seeds; GA7-d and GA7-m, developing and mature seeds of transgenic GA7 line containing a DHA biosynthetic pathway (genes are described in the text). Data are shown as the mean of triplicate analysis with the error bars representing the standard deviations, concentrations (μM) have been determined in the extracts from the same amount of dry seed weight for both developing and mature seeds.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4150447&req=5

Figure 2: Total phospholipids in developing and mature Arabidopsis seeds. Phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylinositol (PI) and phosphatidylserine (PS) were determined from triplicate samples with the mean and standard deviation shown. WT-m, Columbia wild type mature seeds; GA7-d and GA7-m, developing and mature seeds of transgenic GA7 line containing a DHA biosynthetic pathway (genes are described in the text). Data are shown as the mean of triplicate analysis with the error bars representing the standard deviations, concentrations (μM) have been determined in the extracts from the same amount of dry seed weight for both developing and mature seeds.

Mentions: LC-MS analysis of the PL was focused on PA, PC, PE, PG, PI, and PS. The major fatty acids from palmitic acid to the end product ω3 DHA in the engineering pathway were analyzed. As shown in Figure 2, PC and PE were the major PL, followed by PA, with very low amounts of PG and PS. The LC-MS analysis confirmed that there were more total PLs in the developing seeds than in the mature seeds of GA7.


Lipidomic analysis of Arabidopsis seed genetically engineered to contain DHA.

Zhou XR, Callahan DL, Shrestha P, Liu Q, Petrie JR, Singh SP - Front Plant Sci (2014)

Total phospholipids in developing and mature Arabidopsis seeds. Phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylinositol (PI) and phosphatidylserine (PS) were determined from triplicate samples with the mean and standard deviation shown. WT-m, Columbia wild type mature seeds; GA7-d and GA7-m, developing and mature seeds of transgenic GA7 line containing a DHA biosynthetic pathway (genes are described in the text). Data are shown as the mean of triplicate analysis with the error bars representing the standard deviations, concentrations (μM) have been determined in the extracts from the same amount of dry seed weight for both developing and mature seeds.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4150447&req=5

Figure 2: Total phospholipids in developing and mature Arabidopsis seeds. Phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylinositol (PI) and phosphatidylserine (PS) were determined from triplicate samples with the mean and standard deviation shown. WT-m, Columbia wild type mature seeds; GA7-d and GA7-m, developing and mature seeds of transgenic GA7 line containing a DHA biosynthetic pathway (genes are described in the text). Data are shown as the mean of triplicate analysis with the error bars representing the standard deviations, concentrations (μM) have been determined in the extracts from the same amount of dry seed weight for both developing and mature seeds.
Mentions: LC-MS analysis of the PL was focused on PA, PC, PE, PG, PI, and PS. The major fatty acids from palmitic acid to the end product ω3 DHA in the engineering pathway were analyzed. As shown in Figure 2, PC and PE were the major PL, followed by PA, with very low amounts of PG and PS. The LC-MS analysis confirmed that there were more total PLs in the developing seeds than in the mature seeds of GA7.

Bottom Line: Metabolic engineering of omega-3 long-chain (≥C20) polyunsaturated fatty acids (ω3 LC-PUFA) in oilseeds has been one of the key targets in recent years.Liquid chromatography-mass spectrometry (LC-MS) was used to characterize the triacylglycerol (TAG), diacylglycerol (DAG) and phospholipid (PL) lipid classes in the transgenic and wild type Arabidopsis seeds at both developing and mature stages.Trace amounts of di-DHA PC and tri-DHA TAG were identified and confirmed by high resolution MS/MS.

View Article: PubMed Central - PubMed

Affiliation: Food Futures National Research Flagship, Commonwealth Scientific and Industrial Research Organisation Canberra, ACT, Australia ; Plant Industry, Commonwealth Scientific and Industrial Research Organisation Canberra, ACT, Australia.

ABSTRACT
Metabolic engineering of omega-3 long-chain (≥C20) polyunsaturated fatty acids (ω3 LC-PUFA) in oilseeds has been one of the key targets in recent years. By expressing a transgenic pathway for enhancing the synthesis of the ω3 LC-PUFA docosahexaenoic acid (DHA) from endogenous α-linolenic acid (ALA), we obtained the production of fish oil-like proportions of DHA in Arabidopsis seed oil. Liquid chromatography-mass spectrometry (LC-MS) was used to characterize the triacylglycerol (TAG), diacylglycerol (DAG) and phospholipid (PL) lipid classes in the transgenic and wild type Arabidopsis seeds at both developing and mature stages. The analysis identified the appearance of several abundant DHA-containing phosphatidylcholine (PC), DAG and TAG molecular species in mature seeds. The relative abundances of PL, DAG, and TAG species showed a preferred combination of LC-PUFA with ALA in the transgenic seeds, where LC-PUFA were esterified in positions usually occupied by 20:1ω9. Trace amounts of di-DHA PC and tri-DHA TAG were identified and confirmed by high resolution MS/MS. Studying the lipidome in transgenic seeds provided insights into where DHA accumulated and combined with other fatty acids of neutral and phospholipids from the developing and mature seeds.

No MeSH data available.