Disease relevance of SUS1

• Under well-aerated conditions sucrose mobilization in the root can proceed almost entirely via invertases without obvious detriment to the plant, but under hypoxia there is a specific requirement for sucrose synthase activity [1].

High impact information on SUS1

• Expression of an Arabidopsis sucrose synthase gene indicates a role in metabolization of sucrose both during phloem loading and in sink organs [2].
• Sucrose synthase, an important enzyme in carbohydrate metabolism, catalyzes the reversible conversion of sucrose and UDP to UDP-glucose and fructose in vitro [2].
• During anaerobiosis the increase in RNA level leads to increased sucrose synthase activity in roots [2].
• Histochemical GUS analysis of Arabidopsis and tobacco plants transformed with a 1.5 kb Asus1 promoter fragment transcriptionally fused to the beta-glucuronidase reporter gene showed that the Asus1 gene is expressed in the phloem of leaves, and in roots [2].
• Two Sus-encoding genes (Sus1 and Sus2) from Arabidopsis thaliana were found to be profoundly and differentially regulated in leaves exposed to environmental stresses (cold stress, drought or O(2) deficiency) [3].

Biological context of SUS1

• We suggest that Sus1 expression is regulated via an ABA-independent signal transduction pathway that is related to the perception of a decrease in leaf osmotic potential during stresses [3].
• The differential stress-responsive regulation of Sus genes in leaves might represent part of a general cellular response to the allocation of carbohydrates during acclimation processes [3].
• The release of the complete genome sequence of Arabidopsis enabled the largest sucrose synthase family described to date, comprising six distinct members, for which expression profiles were not yet available, to be identified [4].
• Structure and expression profile of the sucrose synthase multigene family in Arabidopsis [4].
• Various sugars also influenced the transcript levels of the CitSUS1 and CITSUSA: These results indicate that the CitSUS1 and CitSUSA genes for sucrose synthase in citrus differ markedly in their molecular structure and potential physiological roles [5].

Anatomical context of SUS1

• Our results suggested that sucrose synthase (SuSy), an enzyme involved in the biosynthesis of cellulose, plays key roles in the connection between mitochondria and cellulose synthesis [6].

Associations of SUS1 with chemical compounds

• The expression pattern and regulation of the gene suggest that sucrose synthase is involved in the supply of energy for phloem loading in source tissues, and in metabolization of sucrose in sink tissues after unloading [2].
• Sugar/osmoticum levels modulate differential abscisic acid-independent expression of two stress-responsive sucrose synthase genes in Arabidopsis [3].
• By using various sucrose/mannitol solutions, we demonstrated that Sus1 was up-regulated by a decrease in leaf osmotic potential rather than an increase in sucrose concentration itself [3].

Other interactions of SUS1

• Transcript levels of Sus1 increased on exposure to cold and drought, whereas Sus2 mRNA was induced specifically by O(2) deficiency [3].

References