Exploring novel roles of starch-binding domains in Arabidopsis

SEUNG_J23DTP

We are looking for a motivated student to join the lab of Dr. David Seung (John Innes Centre) to work on an exciting project that aims to uncover the role of a conserved starch-binding domain family in starch degradation in Arabidopsis leaves. Starch is one of the most important natural resources that we obtain from plants. It is a major source of calories in our diet, and a versatile raw material for producing many essential non-food items. However, starch is also of critical importance to plant growth and productivity as it is the primary form of carbohydrate storage in plant metabolism.

Most plants produce starch in leaves during the day using the products of photosynthesis, and degrade it at night to fuel growth and metabolism in the dark. Starch is an ideal storage carbohydrate as it forms semi-crystalline insoluble granules that are osmotically neutral and relatively inert. However, this semi-crystalline structure poses a challenging substrate for starch-degrading enzymes.

In this project, the student will explore a novel mechanism by which starch-binding domains facilitate starch degradation, involving two previously undescribed proteins that bind to starch.

The student will gain experience and knowledge in a broad range of techniques in molecular genetics, gene editing, and biochemistry. They will also train in advanced chemical and physical analyses of starch structure in the laboratory of project collaborator, Dr. Fred Warren (Quadram Institute).

The project will therefore ideally prepare a student for a career in interdisciplinary life science research.

References

Seung D, Soyk S, Coiro M, Maier B, Eicke S, Zeeman SC (2015). PROTEIN TARGETING TO STARCH is required for localising GRANULE BOUND STARCH SYNTHASE to starch granules and for normal amylose synthesis in Arabidopsis. PLOS Biol 13(2): e1002080.

Seung D, Boudet J, Monroe J, Schreier TB, Abt M, Lu KJ, Zanella M, Zeeman SC (2017). Homologs of PROTEIN TARGETING TO STARCH control starch granule initiation in Arabidopsis leaves. Plant Cell 29: 1657-1677.

Chen J*, Hawkins E*, Seung D (2021). Towards targeted starch modification in plants. Current Opinion in Plant Biology 60:102013. https://doi.org/10.1016/j.pbi.2021.102013.

Hawkins E, Chen J, Watson-Lazowski A, Ahn-Jarvis J, Barclay JE, Fahy B, Hartley M, Warren F, Seung D (2021). STARCH SYNTHASE 4 is required for normal starch granule initiation in amyloplasts of wheat endosperm. New Phytologist 230(6):2371-2386. https://doi.org/10.1111/nph.17342.

Watson-Lazowski A, Raven E, Feike D, Hill L, Barclay JE, Smith AM, Seung D (2022). Loss of PROTEIN TARGETING TO STARCH 2 has variable effects on starch synthesis across organs and species. Journal of Experimental Botany. erac268, https://doi.org/10.1093/jxb/erac268.