Agresearch Limited

National Research Council of Canada

Somrutai Winichayakul

Nicholas John Roberts

Richard William Scott

Marissa Roldan

Amy Christina Curran

David Charles Taylor

Elizabeth-France Marillia

Zacharia D'Arcy Beechey-Gradwell

Luke James Cooney

The invention provides a method for reducing water soluble carbohydrate (WSC) in a photosynthetic cells and plants, the method comprising the step of genetically modifying the photosynthetic cells and plants to express a modified oleosin including at least one artificially introduced cysteine to reduce WSC. The applicants have shown that in such cells and plants, there is a strong correlation between reduced WSC and elevated photosynthesis. In addition, WSC is significantly simpler to measure that than the other typically measured characteristics when selecting cells or plants with the most favourable characteristics.

Methods for improving photosynthetic organisms

The invention provides modified DGAT1 proteins that are modified in the N-terminal region upstream of the acyl-Co A binding site. The modified DGAT proteins show enhanced activity, without reduced protein accumulation when expressed in cells. The modified DGAT1 proteins of the invention can be expressed in cells to increase cellular lipid accumulation and/or modify the cellular lipid profile. The invention also provides polynucleotides encoding the modified DGAT1 proteins, cells and compositions comprising the polynucleotides or modified DGAT proteins, and methods using the modified DGAT1 proteins to produce oil.

Enhanced acyltransferase polynucleotides, polypeptides and methods of use

The invention provides a novel DGAT1 protein with improved properties over known DGAT proteins, particularly known DGAT1 proteins from plants. The novel DGAT1 protein of the invention can be expressed in cells to increase cellular lipid accumulation. Expression of the DGAT1 protein of the invention in cells results in a higher level of lipid than any of several other plant DGAT1 proteins tested by the applicants. The invention provides polynucleotides encoding the novel DGAT1 protein of SEQ ID NO:39, constructs, cells, plant, plant parts and progeny comprising the polynucleotides, and methods of use of the polynucleotides and polypeptides of the invention.

Acyltransferase polynucleotides, polypeptides and methods of use

The invention provides chimeric DGAT1 proteins comprising: a) at their N-terminal ends, an N-terminal portion of a first DGAT1 protein, and b) at their C-terminal ends, a C-terminal portion of a second DGAT1 protein. The chimeric DGAT proteins show enhanced activity relative to at least one of the first DGAT1 protein and the second DGAT1 protein. The chimeric DGAT proteins of the invention can be expressed in cells to increase cellular lipid accumulation and/or modify the cellular lipid profile. The invention also provides polynucleotides encoding the chimeric DGAT1 proteins, cells and compositions comprising the polynucleotides or chimeric DGAT1 proteins, and methods using the chimeric DGAT1 proteins to produce oil.

The invention provides modified oleosins, including at least one artificially introduced cysteine, and methods and compositions for producing the modified oleosins. Also provided are polynucleotides encoding the modified oleosins, constructs and host cells comprising the polynucleotides, methods for producing oil bodies comprising the modified oleosins, in vivo and in vitro, and methods for producing oil in host cells and plants. The invention also provides methods for increasing the rate of COassimilation in photosynthetic cells and plants, and involves reducing or preventing lipid recycling, and/or expressing modified oleosins with artificially introduced cysteine residues in the photosynthetic cells and plants. Also provided are methods for increasing oil production in plants, via expression of modified oleosins in the non-photosynthetic tissues/organs of plants. The method also optionally includes the step of extracting the oil from the non-photosynthetic tissues/organs of the plant, or processing the oil rich non-photosynthetic tissues/organs into animal or biofuel feedstocks.

Growing community of inventors

Palmerston North, New Zealand

Somrutai Winichayakul