Forms and functions of Arabidopsis shoot architecture

Even a redwood tree soaring 100 meter above ground was once a tiny seedling of only few centimeters tall, and during the growth the tree would have become a billion times heavier. Despite such staggering changes in size and weight, the body of the living organisms needs to remain intact throughout their life. How do they ensure the physical integrity?

The emerging picture is that cells react to the physical distress and adjust the composition and construction of their own body accordingly [1-3]. In plants, their structural tissues – wood – form where more support is needed (e.g. the stem base), and weight increase can enhance wood formation [4]. Interestingly, the same hormone regulates wood formation and the outgrowth of branches, another important architectural feature that affects the structural stability of plant shoots [5]. Because structural stability is such a strong driving force for organismal growth and development, it is likely to restrict their architectural features.

This project aspires to capture how weight affects plant shoot architecture and how this physical feedback to the organismal development restricts the possible forms that the shoots assume. A student is invited to explore why the plants have the architecture they have – the natural and wider ranges of possible forms – using state-of-art synthetic biology technology (e.g. [6, 7]) to modulate the shoot architecture and test their functional performance. Depending on the background and interests of the student, the project may be biology-focused or involve mechanical modelling and/or fluid dynamics-based functional assessment.

Falling shoots (called ‘lodging’ in agriculture) causes extensive yield loss (e.g. 25-50% for oilseed rape in the UK [8]), and it is worsening as storms become wilder in the changing climate. Besides the fundamental importance to understanding why and how biological organisms have the body plan and architecture they have, this project is likely to provide novel insights into how to prevent structural failure of crops.

The group (Biological Form + Function Lab) studies key design features of living organisms and their functional significance. We have a unique investigative framework to integrate cell and developmental biology and evolution and ecology (i.e. eco-evo-devo) with synthetic biology and biomechanics (e.g. [9, 10]). The group is committed to training of next-generation scientists in diverse contexts who can turn their insights into exciting new projects based on holistic consideration of the challenges at stake, and we will develop projects incorporating trainees’ scientific interests and career plans.

We are part of the UK’s leading bioengineering department (www.imperial.ac.uk/bioengineering), where pioneering research and innovation in synthetic biology, biomechanics, and developmental mechanics takes place. The student will join the vibrant interdisciplinary community of students and researchers, in which engineering methods are applied to understand and innovate with/for living organisms, including the centre for synthetic biology (https://www.imperial.ac.uk/synthetic-biology).

If you are interested in applying, please contact Dr Nakayama with your CV (including contact information for 2-3 references) and personal statement explaining why you wish to gain PhD training and what about this project captivates you.