ViPS Invited Seminar October 2023

John Lunn, Max Planck, Cologne, Germany

Date: 11th October 2023

Time: 13:00

Title: Trehalose 6-phosphate – a sugar signal linking plant development to metabolism

Location: Auditorium K110, Viikki C Building, Latokartanonkaari 5 and remotely via Zoom

Host: Roosa Laitinen

Abstract: Trehalose 6-phosphate (Tre6P) is an essential sugar-signalling metabolite that links many developmental processes, such as embryogenesis, flowering and shoot branching, to the availability of sucrose. Our sucrose-Tre6P nexus model postulates that Tre6P is both a signal and negative feedback regulator of sucrose levels in plant cells. The model envisages a role for Tre6P in sucrose homeostasis in plants that is analogous to the regulation of blood glucose levels by insulin in animals. In source leaves, Tre6P controls sucrose levels by regulating the partitioning of photoassimilates during the day and the turnover of transitory starch reserves at night. In sink organs, e.g. meristems and axillary buds, Tre6P interacts with phytohormone signalling pathways and links developmental decisions to the availability of sucrose. We are using forward and reverse genetics approaches to dissect the functions of Tre6P in specific tissues, to understand the molecular basis of the sucrose-Tre6P nexus and how Tre6P links the growth and development of the plant to its metabolic status.

The aim of my research is to understand the pathway of carbon in plants, from fixation of atmospheric CO2 by photosynthesis in source leaves to the utilization of fixed carbon for growth in sink organs. We are currently studying the evolution and diversity of photosynthetic metabolism in plants. As partners in the international C4 Rice project (, we are also involved in translational research to introduce the more efficient C4 pathway of photosynthesis into rice, a C3 species, potentially boosting yields by up to 50%. The other main focus of our research is trehalose 6-phosphate (Tre6P)

Read more about John's work

Related publications:

Baena-González E, Lunn JE (2020) SnRK1 and trehalose 6-phosphate – two ancient pathways converge to regulate plant metabolism and growth. Current Opinion in Plant Biology 55; 52–59.

Fichtner F, Barbier FF, Annunziata MG, Feil R, Stitt M, Beveridge CA, Lunn JE (2021) The role of trehalose 6-phosphate in shoot branching – local and non-local effects on axillary bud outgrowth in arabidopsis rosettes. New Phytologist 229; 2135-2151.

Fichtner F, Lunn JE (2021) The role of trehalose 6-phosphate (Tre6P) in plant metabolism and development. Annual Review of Plant Biology 72; 737-760.

Fichtner F, Olas JJ, Feil R, Watanabe M, Krause U, Hoefgen R, Stitt M, Lunn JE (2020) Functional features of TREHALOSE-6-PHOSPHATE SYNTHASE1 – an essential enzyme in Arabidopsis thaliana. The Plant Cell 32; 1949–1972.

Yadav UP, Ivakov A, Feil R, Duan GY, Walther D, Giavalisco P, Piques M, Carillo P, Hubberten HM, Stitt M, Lunn JE (2014) The sucrose-trehalose 6-phosphate (Tre6P) nexus: specificity and mechanisms of sucrose signalling by Tre6P. Journal of Experimental Botany 65; 1051–1068