Trehalose and SnRK signalling pathways: integrators of growth, development and plant stress responses

The trehalose and SnRK1, 2 and 3 signalling pathways regulate many plant processes that contribute to plant survival, growth and development, including processes that contribute to crop yields. In recent years knowledge of the number and range of plant processes regulated by trehalose and SnRK signalling has grown enormously. Trehalose has come from obscurity and can no longer be called a poor relation of sucrose; instead, like sucrose, it is indispensable in growth and development, but as a regulator rather than a substrate. In fact the trehalose pathway is necessary for the utilisation of sucrose. Appreciation of the role of SnRKs has extended beyond metabolism to one of a transcriptional reprogrammer of numerous genes involved in growth and development and stress responses including hormone signalling. SnRKs, like the trehalose pathway, are involved at all stages of plant development from germination through to senescence. It is also clear that there is considerable crosstalk between the trehalose and SnRK signalling networks, consistent with them functioning as signalling partners. They may have coevolved in plants as a means to regulate plant growth and development in relation to carbon supply. For example, while trehalose 6-phosphate attenuates SnRK1 activity and leads to strong changes in SnRK1 marker gene expression, some trehalose pathway signalling may occur independently of SnRK1. Further, SnRK1 also regulates the trehalose pathway.
We welcome all types of articles (original research, methods, hypotheses, opinions and reviews) that provide new insight into these networks, including their regulation, their function in growth and development, plant abiotic and biotic stress responses, and their interactions, as well as potential utility in crop improvement.