EC Number   |
General Information |
Reference |
|---|
   2.4.1.82 | malfunction |
leaves of RFS5 mutant plants fail to accumulate any raffinose under diverse abiotic stresses including water-deficit, high salinity, heat shock, and methyl viologen-induced oxidative stress. Correlated to the lack of raffinose under these abiotic stress conditions, both mutant plants lack the typical stress-induced raffinose synthase activity increase observed in the leaves of wild-type plants |
735861 |
| 2.4.1.82 | malfunction |
metabolite phenotype of DELTAAtRS4 mutant seeds, overview |
-, 736162 |
| 2.4.1.82 | malfunction |
two independent maize (Zea mays) zmrafs mutant lines, in which raffinose is completely abolished, are more sensitive to chilling stress and their net photosynthetic product (total soluble sugars and starch) accumulation is significantly decreased compared with controls after chilling stress. In a mutant of the maize dehydration responsive element (DRE)-binding protein 1A (zmdreb1a), ZmRAFS expression and raffinose content are significantly decreased compared with the control under chilling stress. Overexpression of maize ZmDREB1A in maize leaf protoplasts increases ZmDREB1A amounts, which consequently upregulate the expression of maize ZmRAFS and the Renilla luciferase (Rluc), that is controlled by the ZmRAFS promoter. Deletion of the single dehydration-responsive element (DRE) in the ZmRAFS promoter abolishes ZmDREB1A's influence on Rluc expression, while addition of three copies of the DRE in the ZmRAFS promoter dramatically increases Rluc expression when ZmDREB1A is simultaneously overexpressed. Mutant phenotypes, overview |
-, 759940 |
| 2.4.1.82 | metabolism |
biosynthesis of RFOs proceeds by stepwise transfer of galactosyl units. The second step involves raffinose synthase, AtRS5, EC 2.4.1.82, which transfers the galactosyl unit from galactinol to the C6 position of the glucose unit in sucrose forming an alpha-1,6-galactosidic linkage to yield the trisaccharide raffinose. In a third step, stachyose synthase, AtRS4, EC 2.4.1.67, transfers the galactosyl moiety from galactinol to the C6 position of the galactose unit in raffinose to yield the tetrasaccharide stachyose |
-, 736162 |
| 2.4.1.82 | metabolism |
raffinose synthase (RAFS) is the key enzyme for raffinose biosynthesis |
-, 759940 |
| 2.4.1.82 | metabolism |
the enzyme catalyzes the second step in raffinose biosynthesis |
735861 |
| 2.4.1.82 | more |
changes in soluble carbohydrates (glucose, sucrose, raffinose family oligosaccharides, raffinose and galactinol) in 7-days-old seedling tissues during dehydration for 24 h, overview |
-, 736692 |
| 2.4.1.82 | physiological function |
AtRS4 is the only stachyose synthase in the genome of Arabidopsis thaliana. It represents a key regulation mechanism in the raffinose family oligosaccharide physiology of Arabidosis thaliana due to its multifunctional enzyme activity. AtRS4 is possibly the second seed-specific raffinose synthase beside AtRS5, which is responsible for raffinose accumulation under abiotic stress |
-, 736162 |
| 2.4.1.82 | physiological function |
enzyme is involved in stress resistance |
706178 |
| 2.4.1.82 | physiological function |
in seeds of the galactinol synthase GS1/GS2 and raffinose synthase RFS5 mutant the timing of desiccation tolerance acquisition is delayed as compared to wild type. Seeds from GS1/GS2 overexpressing plants with high levels of galactinol, raffinose, and stachyose, and RS5 overexpressing plants possess more raffinose and stachyose but less galactinol compared to wild type. These lines show greater germination percentage and shorter time to 50% germination after desiccation treatment at 11 and 15 days after flower. The role of raffinose family oligosaccharides is time limited and mainly affects the middle stage of seed development by enhancing seed viability and the ratio of GSH to GSSH in cells, but there is no significant difference in desiccation tolerance of mature seeds |
757498 |
