EC Number   |
General Information |
Reference |
|---|
   2.4.1.242 | malfunction |
a null mutation of the Wx gene in each of the three genomes is associated with starch almost entirely consisting of the branched glucan polymer amylopectin (waxy starch), with corresponding changes in functionality |
759036 |
| 2.4.1.242 | physiological function |
Arabidopsis thaliana mutants lacking plastidial protein PTST synthesise amylose-free starch and are phenotypically similar to mutants lacking granule-bound starch synthase GBSS. PTST mutant starch granules show a dramatic reduction of GBSS protein. GBSS physically interacts with PTST via a coiled coil. The carbohydrate binding module of PTST, which mediates its interaction with starch granules, is also required for correct GBSS localisation. Arabidopsis GBSS requires the presence of Arabidopsis PTST to localise to starch granules. Mutation of the carbohydrate binding module of PTST causes GBSS to remain in the plastid stroma |
737059 |
| 2.4.1.242 | malfunction |
Arabidopsis thaliana ptst mutants synthesise amylose-free starch and are phenotypically similar to mutants lacking GBSS. Mutation of the CBM domain of PTST causes GBSS to remain in the plastid stroma |
737059 |
| 2.4.1.242 | more |
differences in the debranched starch molecular size distribution between Ilpumbyeo and Goami 2 are similar between Nipponbare and ami-BEIIb, a transgenic line with downregulated SBEIIb |
-, 722433 |
| 2.4.1.242 | more |
differences in the debranched starch molecular size distribution between indica variety IR36 and its SBEIIb mutant, IR36ae, which has more amylose chains than IR36 due to more active GBSSI |
-, 722433 |
| 2.4.1.242 | evolution |
diversification of GBSS genes in plants, overview |
723548 |
| 2.4.1.242 | physiological function |
expression of GBSS genes is likely related to starch accumulation in fruit |
723548 |
| 2.4.1.242 | physiological function |
GBSS is responsible for the biosynthesis of the amylose |
706746 |
| 2.4.1.242 | physiological function |
GBSS1 can form oligomers in rice endosperm, and oligomerized OsGBSS1 exhibits much higher specific enzymatic activity than the monomer. A monomer-oligomer transition equilibrium occurs in the endosperm during development. Redox potential is a key factor affecting the oligomer percentage as well as the enzymatic activity. Adenosine diphosphate glucose, the direct donor of glucose, also impacts GBSS1 oligomerization in a concentration-dependent manner. GBSS1 oligomerization is influenced by phosphorylation status, which is strongly enhanced by mitogen-activated protein kinase MAPK and ATP treatment and is sharply weakened by protein phosphatase treatment |
-, 737040 |
| 2.4.1.242 | physiological function |
GBSS1 is the key enzyme in amylose synthesis and exclusively controls all enzyme activities in this pathway, overview. GBSS1 activity is increased compared to wild-type when soluble starch synthases SS2 and SS1 are missing, and the total amount of amylose in the leaves is elevated, SS1 and SS2 activity both can influence the activity of GBSS1 |
720128 |
