Understanding how plants grow and adapt to their environment requires insight into how they connect their internal metabolism with developmental decisions. Plants constantly adjust their growth depending on how much energy and carbon they have available, for example from sugars produced by photosynthesis.

One key molecule involved in this coordination is trehalose 6-phosphate (Tre6P). Tre6P is not used as an energy source itself; instead, it acts as a signal that informs the plant about its sugar status. In particular, Tre6P closely reflects the levels of sucrose, the main sugar that plants transport from photosynthetic tissues (such as leaves) to growing organs (such as roots, buds, and seeds).

Tre6P serves two connected roles. First, its concentration rises and falls with sucrose availability, allowing the plant to sense how much carbon is available for growth. Second, Tre6P also feeds back on sucrose levels, helping to prevent excessive accumulation or depletion of this important sugar. In this way, Tre6P contributes to maintaining a stable balance of sugars within the plant. This feedback control is conceptually similar to how the insulin–glucagon system regulates blood glucose levels in humans and animals. Because sucrose is the central currency for carbon in most land plants, Tre6P plays a pivotal role in ensuring that carbon resources are allocated efficiently between different organs and developmental processes. Through this signalling function, Tre6P directly links plant metabolism with growth, development, and overall performance.

The importance of Tre6P is underscored by the fact that it is essential for plant survival. In the model plant Arabidopsis thaliana, mutations in the gene encoding the main Tre6P-producing enzyme, TREHALOSE-6-PHOSPHATE SYNTHASE 1 (TPS1), are lethal at the embryo stage, demonstrating that plants cannot develop without Tre6P. Using genetically tagged versions of TPS1, we have shown that Tre6P synthesis is not evenly distributed throughout the plant (TPS1 expression shown in blue). Instead, it is concentrated in meristematic tissues, such as the shoot apical meristem and axillary meristems, where new organs are formed, as well as in the vascular system of shoots and roots, which is responsible for long-distance transport of sugars. This spatial pattern supports the idea that Tre6P functions as a key systemic signal, coordinating growth and development with carbon availability across the entire plant.

Changing the levels of Tre6P has profound effects on plant metabolism and development. When Tre6P levels are altered, plants reorganize how they use and distribute their sugars, which leads to visible changes in key traits such as flowering time, shoot branching, and root growth. 

The ability of Tre6P to move information across the plant and to regulate development in a coordinated, whole-plant manner suggests that it behaves similarly to a phytohormone-like signalling molecule. 

Land plants evolved from streptophyte algae ~500 million years ago, requiring new mechanisms to cope with life on land. Tre6P is not only a sugar signal but also a key intermediate in trehalose biosynthesis, a stress-protective sugar that may have supported early land adaptation.

While Tre6P-related genes are present across all green plants, they expanded and diversified with the emergence of vascular tissues, suggesting an important role in long-distance sugar signalling and developmental coordination. We investigate conserved and lineage-specific Tre6P signalling mechanisms across the green lineage using comparative experimental and modelling approaches.

My vision is to understand the fundamental mechanisms that link plant metabolism to plant growth. 

If you are keen to explore that vision and are interested in joining the Tre6P Team, then get in contact! 

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