1 / 24

Plant Sunscreen: The Formation of Sinapoylmalate by O -Methyl Transferases

Plant Sunscreen: The Formation of Sinapoylmalate by O -Methyl Transferases. Beth Kauffman Under the Guidance of: Nick Anderson and Clint Chapple. Outline. Why are methyltransferases important? What is the phenotype of an atomt1 mutant

dewei
Download Presentation

Plant Sunscreen: The Formation of Sinapoylmalate by O -Methyl Transferases

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Plant Sunscreen: The Formation of Sinapoylmalate by O-Methyl Transferases BethKauffman Under the Guidance of: Nick Anderson and Clint Chapple

  2. Outline • Why are methyltransferases important? • What is the phenotype of an atomt1 mutant • How is a candidate COMT tested for redundant ATOMT1 activity? • Do any of the candidate COMT’s have redundant activity? • Future Directions?

  3. Methylation is a common reaction in nature Methyl Donor Methyltransferase Methyl Donor Methyltransferase

  4. O-Methyltransferases are involved in the formation of flavor and scent compounds Vanillin

  5. O-Methyltransferases are involved in the formation of pharmaceuticals Noscapine

  6. O-Methyltransferases are involved in the formation of pigments Malvidin

  7. O-Methyltransferases have various functional properties

  8. A short Life cycle and small genome make Arabidopsis a model organism • Model organism

  9. A short Life cycle and small genome make Arabidopsis a model organism • Model organism • Small genome which has been sequenced • Short life cycle compared to other plants • Relatively easy to make a mutation

  10. Sinapoylmalate acts as a UV protectant in Arabidopsis Ultra Violet Light White Light

  11. A Caffeic Acid O-Methyltransferase (COMT), ATOMT1 participates in the phenylpropanoid pathway. sinapoylmalate atomt1 ATOMT1 sinapylaldehyde phenylalanine 5-OH coniferaldehyde 5-OH feruloylmalate S-lignin

  12. ATOMT1 is required for S-Lignin and sinapoylmalate formation WT atomt1

  13. O-methyltransferases may be responsible Sinapoylmalate formation in an atomt1 mutant • S-lignin falls below level of detection • Sinapoylmalate is still formed. • Arabidopsis has many candidate COMT genes

  14. Candidate COMT’s are investigated using a reverse genetic approach Disruption Gene comt1 atomt1 comt8 atomt1 comt2 atomt1 atomt1 comt9 comt3 atomt1 atomt1 comt10 atomt1 comt4 comt5 atomt1 comt11 atomt1 atomt1 atomt1 comt12 comt6 comt13 atomt1 comt7 atomt1

  15. HPLC analysis is used to quantify soluble metabolite levels • Determined metabolic Profile of HPLC Analysis • If an COMT was responsible, then the mutant’s metabolic profile would contain no sinapoylmalate.

  16. HPLC analysis is used to quantify soluble metabolite levels • Determined metabolic Profile of HPLC Analysis • If an COMT was responsible, then the mutant’s metabolic profile would contain no sinapoylmalate. 5-OH feruloylmalate sinapoylmalate

  17. Candidate COMT’s not consistent with redundant ATOMT1 activity WT atomt1

  18. Candidate COMT’s not consistent with redundant ATOMT1 activity WT atomt1 comt/atomt1

  19. Future Directions • It may be that a combination of several COMT’s are responsible for the redundant activity • Triple mutants generated • Same method of study conducted with triple mutants. If a triple mutant does not form sinapoylmalate, then combination is responsible comt2 atomt1 comt1

  20. Chapple Lab Nick Anderson Clint Chapple Jo Cusumano Nick Bonawitz Jeong-Im Kim Peng Wang Yi Li Whitney Dolan WenjieZeng Marwa El-Hindawy Alexandra Smith Nicholas Pogranichniy Misha Remy Acknowledgements

  21. References • Besse, P., Da Silva, D., Bory, S., Noirot, M., and Grissoni, M.(2009). Variation in intron length in caffeic acid O-methyltransferase (COMT) in Vanilla species (Orchidaceae). Plant Sci. 176, 452-460. • Goujon, T., Sibout, R., Pollet, B., Maba, B., Nussaume, L., et. al. (2003). A new Arabidopsis thaliana mutant deficient in the expression of O-methyltransferase impacts lignins and sinapoylesters.Plant. Mol. Bio.51, 973-989. • Do, C., Pollet, B., Thevenin, J., Sibout, R., Denoue, D., et. al. (2007). Both caffeoul Coenzyme A 3-O-methyltransferase 1 and caffeic acid O-methyltransferase 1 are involved in redundant functions for lignin, flavonoids and sinapoylmalate biosynthesis in Arabidopsis. Planta.226, 1117-1129. • Dang, T. T., and Facchini, P. J. (2012). Characterization of Three O-Methyltransferases Involved in Noscapine Biosynthesis in Opium Poppy. Plant Phys.159, 618-631.

  22. O-Methyltransferases Have Various Functional Properties 3,5-dimethoxytoluene

  23. O-Methyltransferases Have Various Functional Properties Guaicol

More Related