Starch synthase 4 is essential for coordination of starch granule formation with chloroplast division during Arabidopsis leaf expansion
| Autor: | Matilda Crumpton-Taylor, Alison M. Smith, Christopher M. Hylton, Marilyn J. Pike, Regina Feil, Kuan-Jen Lu, John E. Lunn, Simona Eicke, Samuel C. Zeeman |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
0106 biological sciences
Heterozygote Chloroplasts Arabidopsis thaliana Physiology Starch leaf expansion Mutant Arabidopsis Agrobacterium Plant Science 01 natural sciences Isozyme starch synthase Adenosine Diphosphate Glucose 03 medical and health sciences chemistry.chemical_compound chloroplast Glycogen synthase Glucans starch synthesis 030304 developmental biology 0303 health sciences biology Arabidopsis Proteins Research Granule (cell biology) food and beverages ADPglucose Chloroplast Leaf expansion Starch granule Starch synthase Starch synthesis biology.organism_classification Isoenzymes Plant Leaves Glycogen Synthase Biochemistry chemistry Solubility Mutation Organelle Size biology.protein Metabolome RNA Interference starch granule 010606 plant biology & botany |
| Zdroj: | The New Phytologist New Phytologist, 200 (4) New Phytologist |
| ISSN: | 1469-8137 0028-646X |
| Popis: | Arabidopsis thaliana mutants lacking the SS4 isoform of starch synthase have strongly reduced numbers of starch granules per chloroplast, suggesting that SS4 is necessary for the normal generation of starch granules. To establish whether it plays a direct role in this process, we investigated the circumstances in which granules are formed in ss4 mutants. Starch granule numbers and distribution and the accumulation of starch synthase substrates and products were investigated during ss4 leaf development, and in ss4 mutants carrying mutations or transgenes that affect starch turnover or chloroplast volume. We found that immature ss4 leaves have no starch granules, but accumulate high concentrations of the starch synthase substrate ADPglucose. Granule numbers are partially restored by elevating the capacity for glucan synthesis (via expression of bacterial glycogen synthase) or by increasing the volumes of individual chloroplasts (via introduction of arc mutations). However, these granules are abnormal in distribution, size and shape. SS4 is an essential component of a mechanism that coordinates granule formation with chloroplast division during leaf expansion and determines the abundance and the flattened, discoid shape of leaf starch granules. New Phytologist, 200 (4) ISSN:0028-646X ISSN:1469-8137 |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text