Stabilization of rubisco activase for enhanced photosynthesis and crop yields
A modified rubisco activase, wherein the modified rubisco activase has a melting temperature greater than that of wild type rubisco activase. Further aspects of the disclosure relate to an isolated polynucleotide encoding a modified rubisco activase and a recombinant expression system comprising the isolated polynucleotide. Still further aspects of the disclosure relate to a plant cell transfected with the recombinant expression system. Certain aspects of the disclosure relate to a genetically modified plant expressing the isolated polynucleotide encoding a modified rubisco activase.
1. A modified rubisco activase comprising a point mutation at amino acid positions 135 or 163 based on the sequence according to SEQ ID NO: 31, wherein the modified rubisco activase has a melting temperature greater than about 30.4° C.
2. The modified rubisco activase of claim 1 , wherein the point mutation at amino acid position 135 results in a substitution of R for the naturally occurring amino acid at this position, wherein the point mutation at amino acid position 163 results in a substitution of I for the naturally occurring amino acid at this position.
3. The modified rubisco activase of claim 1 , wherein the modified rubisco activase further comprises a point mutation at amino acid position 262 based on the sequence according to SEQ ID NO: 31.
4. The modified rubisco activase of claim 1 , wherein the modified rubisco activase is soy β rubisco activase.
5. The modified rubisco activase of claim 2 , wherein the modified rubisco activase comprises the point mutations at amino acid positions 135, 163, and further comprises a point mutation at amino acid position 262 according to SEQ ID NO: 31, wherein the point mutation at amino acid position 262 results in a substitution of I for the naturally occurring amino acid at this position.
6. The modified rubisco activase of claim 2 , wherein the modified rubisco activase comprises point mutations at positions 135 and 163 based on the sequence according to SEQ ID NO: 31.
7. The modified rubisco activase of claim 1 , wherein the modified rubisco activase is Miscanthus β rubisco activase according to SEQ ID NO: 2, and wherein the amino acid positions 135 and 162 based on SEQ ID NO: 31 respectively correspond to amino acid positions 133 and 161 in SEQ ID NO: 2.
8. The modified rubisco activase of claim 7 , wherein the modified rubisco activase has a melting temperature greater than about 39.8° C.
9. The modified rubisco activase of claim 7 , wherein the point mutation at amino acid position 133 results in a substitution of R for the naturally occurring amino acid at this position, wherein the point mutation at amino acid position 161 results in a substitution of I for the naturally occurring amino acid at this position.
10. The modified rubisco activase of claim 7 , wherein the modified rubisco activase comprises point mutations at amino acid positions 133 and 161, and further comprises a point mutation at position 260 in SEQ ID NO: 2 that corresponds to position 262 according to SEQ ID NO: 31.
11. The modified rubisco activase of claim 1 , wherein the modified rubisco activase has a melting temperature greater than about 34.5° C.
12. The modified rubisco activase of claim 1 , wherein the modified rubisco activase has a melting temperature greater than about 34.9° C.
13. The modified rubisco activase of claim 1 , wherein the modified rubisco activase has a melting temperature greater than about 38.8° C.
14. The modified rubisco activase of claim 1 , wherein the modified rubisco activase has a melting temperature greater than about 42.8° C.
15. The modified rubisco activase of claim 1 , wherein the modified rubisco activase has a melting temperature greater than about 44.0° C.
16. The modified rubisco activase of claim 1 , wherein the modified rubisco activase has a melting temperature greater than about 44.4° C.
17. The modified rubisco activase of claim 1 , wherein the modified rubisco activase has a melting temperature greater than about 46.0° C.
18. An isolated polynucleotide encoding the modified rubisco activase of claim 1 .
19. A recombinant expression system comprising the isolated polynucleotide of claim 18 .
20. A plant cell transfected with the recombinant expression system of claim 19 .
21. A genetically modified plant expressing the isolated polynucleotide of claim 18 .
22. The genetically modified plant of claim 21 , wherein the genetically modified plant is a genetically modified Arabidospis.
23. The genetically modified plant of claim 21 , wherein the genetically modified plant is a genetically modified soybean plant.
24. The genetically modified plant of claim 21 , wherein the genetically modified plant is a genetically modified Miscanthus giganteus.