Diacylglycerol acyltransferase 2 genes and proteins encoded thereby from algae
View Patent ↗The present disclosure relates to the isolation, purification, and characterization of a diacylglycerol acyltransferase 2 (DGAT2), and genes encoding DGAT2, from algae. DGAT2 can incorporate very long chain polyunsaturated fatty acids in to triacylglycerol more efficiently than DGAT1. The disclosure concerns methods of regulating seed oil content, fatty acid synthesis and fatty acid composition using the DGAT2 gene and to tissues and plants transformed with the gene. The disclosure also relates to transgenic plants, plant tissues and plant seeds having a genome containing an introduced DNA sequence of the disclosure, and a method of producing such plants and plant seeds.
1. An isolated polypeptide comprising a peptide having at least 90% sequence identity to SEQ ID NO:15, wherein the polypeptide has diacylglycerol acyltransferase activity.
2. The isolated polypeptide of claim 1 , wherein the polypeptide has at least 90% sequence identity to SEQ ID NO:1.
3. A nucleic acid molecule comprising a heterologous promoter operably linked to a polynucleotide encoding a polypeptide comprisinq a peptide having at least 90% sequence identity to SEQ ID NO:15, wherein the encoded polypeptide has diacylglycerol acyltransferase activity.
4. A vector comprising a polynucleotide encoding a polypeptide comprising a peptide having at least 90% sequence identity to SEQ ID NO:15, wherein the encoded polypeptide has diacylglycerol acyltransferase activity.
5. A transgenic plant cell comprising the nucleic acid molecule of claim 3 .
6. A yeast cell transformed with the nucleic acid molecule of claim 3 .
7. A method of altering levels of very long chain polyunsaturated fatty acids in a plant, the method comprising:
introducing into the plant the nucleic acid molecule of claim 3 .
8. The method according to claim 7 , wherein the nucleic acid molecule is introduced into the plant by Agrobacterium -mediated transformation.
9. The method according to claim 7 , wherein the method further comprises
introducing into the plant a polynucleotide encoding a polypeptide with pyruvate dehydrogenase
kinase activity.
10. The method according to claim 7 , wherein the method further comprises
introducing into the plant a polynucleotide encoding a polypeptide with diacylglycerol acetyltransferase activity.
11. The method according to claim 7 , wherein the method further comprises
introducing into the plant a polynucleotide encoding a polypeptide with glycerol-3-phosphate
dehydrogenase activity.
12. The method according to claim 7 , wherein the plant is selected from the group consisting of Arabidopsis thaliana, Borago spp., Canola, Ricinus spp., Theobroma spp., Zea spp., Gossypium spp, Crambe spp., Cuphea spp., Linum spp., Lesquerella spp., Limnanthes spp., Linola, Tropaeolum spp., Oenothera spp., Olea spp., Elaeis spp., Arachis spp., rapeseed, Carthamus spp., Glycine spp., Soja spp., Helianthus spp., Nicotiana spp., Vernonia spp., Triticum spp., Hordeum spp., Oryza spp., Avena spp., Sorghum spp., Secale spp., Brassicaceae, and other members of the plant family Gramineae.
13. A plant produced by a method comprising introducing into the plant a nucleic acid molecule encoding a polypeptide comprising a peptide having at least 90% sequence identity to SEQ ID NO:15.
14. A seed harvested from the plant of claim 13 , wherein the seed comprises a polynucleotide encoding a polypeptide comprising a peptide having at least 90% sequence identity to SEQ ID NO:15, wherein the encoded polypeptide has diacylglycerol acyltransferase activity.
15. The method according to claim 7 , wherein the method comprises:
harvesting a seed from the plant; and
extracting oil from the harvested seed.
16. A transgenic plant comprising the plant cell of claim 5 .
17. The method according to claim 9 , wherein the polypeptide with pyruvate dehydrogenase kinase activity is from a plant of the genus Brassica.
18. The transgenic plant of claim 16 , wherein the transgenic plant is a Brassica plant, and wherein the plant has altered levels of polyunsaturated fatty acids in seeds as compared to levels in a plant of the same species lacking the polynucleotide.
19. The transgenic plant of claim 16 , wherein the transgenic plant is a
Brassica plant, and wherein the fatty acids in the plant are more than 70% polyunsaturated
fatty acids.