arabidopsis; starch metabolism; amylopectin structure; debranching enzyme; functional genomics; structural biology; bonus-of-excellence
Ragel Paula, Streb Sebastian, Feil Regina, Sahrawy Mariam, Annunziata Maria Grazia, Lunn John E, Zeeman Samuel, Merida Angel (2013), Loss of Starch Granule Initiation Has a Deleterious Effect on the Growth of Arabidopsis Plants Due to an Accumulation of ADP-Glucose, in Plant Physiology
, 163, 75-85.
Crumpton-Taylor Matilda, Pike Marilyn, Lu Kuan-Jen, Hylton Christopher M., Feil Regina, Eicke Simona, Lunn John E., Zeeman Samuel C., Smith Alison M. (2013), Starch synthase 4 is essential for coordination of starch granule formation with chloroplast division during Arabidopsis leaf expansion, in New Phytologist
, 200, 1064-1075.
Sundberg Maria, Pfister Barbara, Fulton Daniel, Bischof Sylvain, Delatte Thierry, Eicke Simona, Stettler Michaela, Smith Steven M., Streb Sebastian, Zeeman Samuel C. (2013), The Heteromultimeric Debranching Enzyme Involved in Starch Synthesis in Arabidopsis Requires Both Isoamylase1 and Isoamylase2 Subunits for Complex Stability and Activity, in PLoS ONE
, 8(9), e75223.
Streb Sebastian, Zeeman Samuel C (2012), Starch Metabolism in Arabidopsis, in The Arabidopsis Book
, 10, e0160.
Streb Sebastian, Eicke Simona, Zeeman Samuel C (2012), The Simultaneous Abolition of Three Starch Hydrolases Blocks Transient Starch Breakdown in Arabidopsis, in Journal of Biological Chemistry
, 287(50), 41745-41756.
This work aims to understand the biosynthesis and degradation of starch, the predominant storage carbohydrate in plants. Starch is important because it is the single largest component of our nutrition, and a large fraction of our arable land is given over to the growth of starch crops. Starch is made primarily of branched glucans that form insoluble glucans. In the previous granting periods we have conducted an extensive analysis of starch debranching enzyme (DBE) functions in the model plant Arabidopsis, which makes starch in its leaves. We have shown that one specific heteromultimeric DBE facilitates starch biosynthesis, while two other monomeric DBEs function primarily in starch breakdown. Mutants lacking the heteromultimeric DBE accumulate a soluble glycogen-like polymer rather than starch. This proposal aims to further our understanding of the starch biosynthetic process and the structure-functional relationship of the heteromultimeric DBE.