Trehalose-6-phosphate: connecting plant metabolism and development.

Jathish Ponnu,Markus Schmid,Vanessa Wahl

doi:10.3389/fpls.2011.00070

Jathish Ponnu, Markus Schmid + Show 1 more

Open Access

https://doi.org/10.3389/fpls.2011.00070

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Abstract

Beyond their metabolic roles, sugars can also act as messengers in signal transduction. Trehalose, a sugar found in many species of plants and animals, is a non-reducing disaccharide composed of two glucose moieties. Its synthesis in plants is a two-step process, involving the production of trehalose-6-phosphate (T6P) catalyzed by trehalose-6-phosphate synthase (TPS) and its consecutive dephosphorylation to trehalose, catalyzed by trehalose-6-phosphate phosphatase (TPP). T6P has recently emerged as an important signaling metabolite, regulating carbon assimilation and sugar status in plants. In addition, T6P has also been demonstrated to play an essential role in plant development. This review recapitulates the recent advances we have made in understanding the role of T6P in coordinating diverse metabolic and developmental processes.

Highlights

Plants convert assimilated carbon into a range of monosaccharide sugars, many of which serve as precursors for the synthesis of more complex oligo- and polysaccharides
A sugar found in many species of plants and animals, is a non-reducing disaccharide composed of two glucose moieties
The effects on sucrose non-fermenting 1related protein kinase1 (SnRK1) activity seem to be specific to T6P, as none of the other tested sugars or sugar phosphates inhibited SnRK1 (Zhang et al, 2009). These experiments provide strong evidence that T6P inhibits SnRK1 to activate biosynthetic processes in growing tissues. These results suggest a regulatory loop in which sucroseinduced T6P inhibits SnRK1 when sucrose is plentiful

Summary

INTRODUCTION

Plants convert assimilated carbon into a range of monosaccharide sugars, many of which serve as precursors for the synthesis of more complex oligo- and polysaccharides These complex carbohydrates fulfill very diverse functions in plants and are, for example, used as long-term energy storage or constitute important structural components of plant cells. The regulation of plant development by carbohydrates has attracted a lot of interest over the last few years and several signaling pathways that integrate sugar responses have been identified One such pathway involves the synthesis, perception, and response to the non-reducing disaccharide trehalose and its precursor trehalose-6phosphate (T6P). AtTPS1 expression has been detected by qRT-PCR in flower buds, ripening siliques, small rosette leaves, and in embryos using a TPS1-GUS reporter (van Dijken et al, 2004; Gómez et al, 2010). All TPPs lack the N-terminal TPS-like domain found in the TPS proteins and contain only the conserved TPP domain, which www.frontiersin.org

Class II TPPs Trehalase

CONCLUSION AND PERSPECTIVE