Trehalose 6-phosphate is indispensable for carbohydrate utilization and growth in Arabidopsis thaliana

Abstract

Genes for trehalose metabolism are widespread in higher plants. Insight into the physiological role of the trehalose pathway outside of resurrection plant species is lacking. To address this lack of insight, we express Escherichia coli genes for trehalose metabolism in Arabidopsis thaliana, which manipulates trehalose 6-phosphate (T6P) contents in the transgenic plants. Plants

The Energy-Signaling Hub SnRK1 Is Important for Sucrose-Induced Hypocotyl Elongation

“…Although hypocotyl elongation arises from cell expansion rather than growth through increases in cell number (Gendreau et al, 1997), our data are consistent with studies demonstrating that Tre6P metabolism is a crucial regulator of growth responses to Suc. For example, Arabidopsis seedlings overexpressing the bacterial Tre6P phosphatase otsB, which reduces [Tre6P], accumulate less biomass compared with the wild type when supplemented with Suc (Schluepmann et al, 2003). The converse is also true; otsA (TPS) overexpressors, in which [Tre6P] is increased, accumulate more biomass than the wild type when supplemented with Suc (Schluepmann et al, 2003).…”

“…For example, Arabidopsis seedlings overexpressing the bacterial Tre6P phosphatase otsB, which reduces [Tre6P], accumulate less biomass compared with the wild type when supplemented with Suc (Schluepmann et al, 2003). The converse is also true; otsA (TPS) overexpressors, in which [Tre6P] is increased, accumulate more biomass than the wild type when supplemented with Suc (Schluepmann et al, 2003). Therefore, our data using tps1 mutants as a proxy for altered Tre6P metabolism provide new evidence to support the notion that Tre6P promotes growth under conditions of increased Suc availability (Schluepmann et al, 2003;Zhang et al, 2009).…”

“…Signaling by Tre6P and KIN10 is also important for the regulation of growth rates. Growth is increased by Suc in the presence of Tre6P (Schluepmann et al, 2003;Paul et al, 2010), but the lack of a quantitative (correlative) relationship between relative growth rates and [Tre6P] suggests that a threshold [Tre6P] is required for growth to occur (Nunes et al, 2013a(Nunes et al, , 2013b. Therefore, it has been suggested that control of KIN10/11 by [Tre6P] may prime the regulation of growth-related genes to capitalize upon increased energy availability, rather than by inducing growth directly (Nunes et al, 2013a(Nunes et al, , 2013b.…”

A bifunctional TPS–TPP enzyme from yeast confers tolerance to multiple and extreme abiotic-stress conditions in transgenic Arabidopsis

“…It has been shown that T6P has a regulatory role in carbohydrate utilization during plant growth and development (Eastmond et al 2002;Schluepmann et al 2003Schluepmann et al , 2004van Dijken et al 2004). We have reported before that overexpression in Arabidopsis of its AtTPS1 homolog leads to a glucose and abscisic-acid insensitive phenotype and to stress tolerance, suggesting that trehalose metabolism plays an important role in signaling gene regulation to integrate environmental and metabolic cues during vegetative development (Avonce et al 2004).…”

“…Overexpression of the Arabidopsis AtTPS1 gene in its homologous background does not produce such drastic eVects but still there is a delay in Xowering (Avonce et al 2004). The accumulation of higher levels of T6P are probably causing these defects since T6P has turned out to be a Wne-tuned signaling molecule that has a regulatory role in carbohydrate utilization during plant growth, embryo development and Xowering (Eastmond et al 2002;Schluepmann et al 2003Schluepmann et al , 2004van Dijken et al 2004). Therefore, it was decided to construct a bifunctional TPS-TPP enzyme, which while maintaining trehalose biosynthesis capacity would not lead to excess accumulation of free T6P in the cytosol avoiding undesired secondary eVects in the transgenic plants.…”