The trehalose sugar plays pivotal roles in plants. In Arabidopsis, trehalose supplied to the medium leads to starch accumulation through redox activation of the ADP-glucose pyrophosphorylase (AGPase) by the NADPH-dependent thioredoxin reductase C (NTRC). To gain further insight on the regulation of carbohydrate metabolism by trehalose and NTRC, Arabidopsis wild-type (wt) and ntrc plants were raised in the MS medium supplemented with or without 100-mM sucrose or trehalose and alterations in sugar and starch contents as well as the activities and expressions of some carbohydrate metabolizing enzymes were investigated. The ntrc plants displayed lower growth rate compared to wt by sugar feeding. Under trehalose treatment, the total soluble, reducing and non-reducing sugars of wt and ntrc plants decreased between end of the day and end of the night, but starch in the ntrc plants remained unaltered during the aforementioned period. The obtained data showed that trehalase activity and gene expression display diurnal rhythms. Meanwhile, under darkness, trehalase gene expression required functional NTRC. Trehalose feeding induced NTRC expression during the day, but suppressed it during the night. Moreover, AGPase expression found to be jointly regulated by carbon nutrition and the light–dark period in both wt and mutant plants. The current data also revealed that AMY3 (α-amylase 3) gene expression depends on the presence of functional NTRC in plants. It seems that cross-talk between trehalose and NTRC regulates diurnal carbohydrate metabolism in plants.

海藻糖在植物中起关键作用。在拟南芥中，提供给培养基的海藻糖通过NADPH依赖性硫氧还蛋白还原酶C（NTRC）对ADP-葡萄糖焦磷酸化酶（AGPase）的氧化还原激活而导致淀粉积累。为了进一步了解海藻糖和NTRC对碳水化合物代谢的调控，在添加或不添加100mM蔗糖或海藻糖的MS培养基中培育了拟南芥野生型（wt）和ntrc植物，以及糖和淀粉含量的变化研究了某些碳水化合物代谢酶的活性和表达。所述NTRC与由糖馈送wt植物显示较低的生长速率。在海藻糖处理下，wt和wt的总可溶性，还原性和非还原性糖ntrc植物在白天到深夜之间减少，但在上述期间，ntrc植物中的淀粉保持不变。获得的数据表明海藻糖酶活性和基因表达表现出昼夜节律。同时，在黑暗中，海藻糖酶基因表达需要功能性NTRC。海藻糖喂养在白天诱导NTRC表达，但在夜间抑制它。此外，在野生型和突变型植物中，发现AGPase的表达均受碳营养和光暗期的共同调节。目前的数据还显示，AMY3（α-淀粉酶3）基因表达取决于植物中功能性NTRC的存在。海藻糖和NTRC之间的串扰似乎调节了植物中的昼夜碳水化合物代谢。