Compositions and methods for differential regulation of fatty acid unsaturation in membrane lipids and seed oil

摘要

Aspects of the invention provide methods for differential regulation of fatty acid unsaturation in seed oil and membrane lipids of plants based on modulation of a previously unknown biosynthetic pathway involving a novel phosphatidylcholine: diacylglycerol cholinephosphotransferase (PDCT) that regulates phosphatidylcholine biosynthesis in developing oil seed plants. Specific aspects relate to inventive PDCT polypeptides including, for example, variants, deletions, muteins, fusion proteins, and orthologs thereof (collectively PDCT proteins), to nucleic acids encoding same, to plants comprising such PDCT sequences or proteins or devoid or depleted of such PDCT proteins or sequences, and to methods for generating plants having altered or no PDCT expression and/or activity, including but not limited to methods comprising mutagenesis, recombinant DNA, transgenics, etc.

主权项

1. A method for regulation of fatty acid unsaturation in seed oil, comprising:
obtaining an oilseed-bearing plant other than Arabidopsis; and downregulating, using at least one of mutagenesis and recombinant DNA methods, the expression or activity of at least one phosphatidylcholine:diacylglycerol cholinephosphotransferase (PDCT) in one or more seeds or developing seeds of the plant, wherein the level, amount, or distribution of fatty acid unsaturation in the seed oil is reduced relative to the seed oil of plants with normal seed expression of the PDCT, wherein the fatty acid unsaturation in seed oil relative to fatty acid unsaturation in one or more membrane lipids is differentially reduced in seed oil, wherein the at least one of mutagenesis and recombinant DNA method directly downregulates the expression or activity of the at least one PDCT.