Linking the Target of Rapamycin signalling to cell cycle progression during tuber initiation and its impact on potato yield parameters

Potato tubers are nutrient storage organs that develop from underground stems called stolons through a process called tuberisation.

This process is under the control of extrinsic and intrinsic signals, however, little is known about how these signals initiate and maintain tuber growth.

We know that the first step is the initiation of cell division at the subapical region of the stolon, however, how this cell division is promoted and coordinated through developmental programs has not yet been studied.

The TorCrop project will build on knowledge accumulated through fundamental research in model organisms to gain molecular insight in tuber initiation and growth.

For this purpose, we will induce tuber growth by sugar and characterise the cell proliferation and cell growth during tuber formation.

As next step, we will explore how the nutrient sensing Target of Rapamycin (TOR) pathway contributes to this and is there any hierarchical connection between TOR and the “tuberigen” signal.

Then, we will identify quantitative trait loci (QTLs) that define tuber size, size distribution which is connected to enhanced TOR activation.

We will also analyse allelic variations in identified candidate genes and link these to phenotypic variations available from breeding companies and in public databases.

Finally, we will create predictive mathematical models that describe cell size, number and changes throughout tuberisation in relation to tuber size and ultimately yield.

Therefore, the project will provide a better understanding on organ development and ultimately yield in crops by providing knowledge at molecular and systems biology levels.