Plants generate sugars in their leaves (sources) during photosynthesis, which subsequently need to be distributed amongst growing organs such as new, young leaves, flowers, stems and roots as well as storage organs such as potato tubers or fruits (sinks). This sucrose transport depends on the activity of sources and sinks that together determine the osmotic gradients driving vasculature sap transport, with different sources competing for the sucrose. In addition, transport is regulated via long distance signalling molecules that control the activity of cellular sucrose transporters, thereby impacting the relative balance between symplastic (direct cell-to-cell) and apoplastic (cell-to-wall-to-cell) transport routes. Over the course of their development, plants may profoundly change their sugar transport, for example when making storage organs such as tubers they redirect a large part of their sugar transport to these organs. Additionally, depending on environmental conditions, plants may make different decisions on where to invest their sugars, e.g. in flowers for sexual reproduction or rather tubers for asexual reproduction. Exactly how plants reach these decisions, and subsequently rewire their sugar transport remains incompletely understood.

Project
Goal of the current project is to develop detailed computational simulation models of plant sucrose transport, incorporating different involved cell types and tissues, cellular uptake and export transporters and their regulation by signalling factors, symplastic and apoplastic transport routes, and source and sink strength dependent vasculature fluxes. The aim is to obtain an understanding of how plants control the amount of sucrose going to tubers versus other plant organs, for example in the context of investing energy in vegetative reproduction via tubers versus sexual reproduction via flowering. The selected candidate will work in the group of Prof. Kirsten ten Tusscher at the Computational Developmental Biology group at Utrecht University.

 

The PhD position is part of a larger TTW project on potato yield and will be performed in collaboration with the group of Christian Bachem at Wageningen University. Experimental and bioinformatic data obtained in the experimental counterpart of the project will thus serve as input for the modeling, while modeling outcomes will be used to direct future experiments into promising directions. The project is aimed to start in the spring of 2019.

We are looking for motivated candidates with a background in computational biology, computer science, physics or mathematics. Candidates should have a genuine interest in applying mathematical and computational techniques to achieve biological insights, and experience with computer programming and simulation. Additionally, applicants should have excellent English oral, writing and presentation skills. 

The candidate is offered a full-time position for 1 year with an extension for a further three years if the evaluation is positive. The research group will provide the candidate with necessary support on all aspects of the project.

The gross monthly salary starts at €2,266 in the first year, and ends at €2,897 in the fourth year for a full-time employment (scale P Collective Labour Agreement Dutch Universities). Salaries are supplemented with a holiday bonus of 8% and a year-end allowance of 8.3% per year. In addition, Utrecht University offers excellent secondary conditions, including an attractive retirement scheme, (partly paid) parental leave and flexible employment conditions (multiple choice model). Here you'll find more information about working at Utrecht University.

A better future for everyone. This ambition motivates our scientists in executing their leading research and inspiring teaching. At Utrecht University, the various disciplines collaborate intensively towards major societal themes. Our focus is on Dynamics of Youth, Institutions for Open Societies, Life Sciences and Sustainability.

The city of Utrecht is one of the oldest cities in the Netherlands, with a charming old center and an internationally oriented culture that is strongly influenced by its century-old university. Utrecht city has been consistently ranked as one of the most livable cities in the Netherlands.

The Faculty of Science consists of six Departments: Biology, Pharmaceutical Sciences, Information and Computing Sciences, Physics and Astronomy, Chemistry and Mathematics. The Faculty is home to 5,600 students and nearly 1500 staff and is internationally renowned for the quality of its research. The Faculty's academic programmes reflect developments in today's society. Read the overall impression 2016 of the Faculty of Science.

The Utrecht Theoretical Biology group is a highly international and collaborative research group, that is home to world-class experts in the area of mathematical, theoretical and computational biology. Applications of biological modeling range from evolution and the origin of life, the immune system, cancer and animal development to plant adaptation.