Dr Sarah Robinson
- Research Group Leader
Contact
Location
- Sainsbury Laboratory
- 47 Bateman Street, Cambridge, CB2 1LR
About
I have always focused on plant development and I enjoy taking an interdisciplinary approach. I completed my PhD at John Innes centre Norwich where I combined modelling and timelapse imaging to study stomatal patterning on leaves. Followed by a post doc in Bern Switzerland where I developed a new method for plant biomechanics. I use it to study plant growth and responses to mechanical stress.
I am now a group leader at Sainsbury Laboratory Cambridge University. I investigate plant development from a biomechanical perspective. We are particularly interested in how cell division changes the mechanical properties of the tissue.
Research
Research interests
- Biomechanics
- Cell division
- Growth
My research focuses on plant development and how growth, cell division and differentiation are coordinated. I am particularly interested in how cell and organ size and shape are determined and am investigating these processes using biomechanics, modelling and genomic approaches.
How dynamic spatial patterns are generated within growing proliferating tissues is crucial to understanding development in multi-cellular organisms. However, this process is poorly understood due to difficulties in unravelling the interactions between the many processes that occur at once. My PhD investigation of this problem involved looking at the patterning of stomata in growing proliferating Arabidopsis leaves at the John Innes Centres under the supervision of Enrico Coen. I followed cell lineages using live confocal time lapse imaging to compare behaviour of wild type plants with the speechless mutant, which does not make stomata. Under the supervision of my co-supervisor Przemyslaw Prusinkiewicz I generated a descriptive model of the spch mutant that provided a framework for investigating the wild-type divisions, which provided an insight into how dynamic spatial patterns can be generated in growing proliferating tissues.
Growth was an ever-present topic during my PhD, and this motivated me to further investigate mechanics in collaboration with experts in this field as an EMBO Research Fellow in the lab of Professor Cris Kuhlemeier at the University of Bern. It was here that I developed new method for studying biomechanics in plant development.
The mechanical properties of the cell wall and their spatial variation are the key factors controlling morphogenesis in plants. However, these properties are difficult to measure and investigating their relation to genetic regulation is particularly challenging. A major issue has been the lack of suitable methods. Traditional extensometers are not suitable for the small developing Arabidopsis tissues and provide low-resolution information. Indentation methods, by contrast, provide very high-resolution information but are restricted to measuring the surface of the epidermis perpendicular to the direction of growth. I, therefore, led the development of a method (ACME) that combines confocal imaging and mechanical manipulations, with the help of an electrical engineer M. Huflejt.
ACME robotic system to measure mechanical properties of living cells
The open-source ACME (Automated confocal micro-extensometer) method (Robinson 2017 et al) was developed to measure the mechanical properties that accompany plant growth. ACME functions like a traditional extensometer, but is miniaturised, mounted on the stage of a confocal microscope, and fully automated. ACME computes the mechanical properties of samples at the cellular level based on changes in features of the tissue itself (tracked in time-lapse z-stack images) during application of a known force or deformation.
I have used the ACME system to measure the changes in the mechanical properties of the individual cells of the developing hypocotyl in an Arabidopsis seedling upon the application of the plant hormone gibberellic acid that promotes growth in the hypocotyl (Robinson et al. 2017). I also used the ACME setup to investigate whether microtubules respond to mechanical stress in Arabidopsis hypocotyls. I was able to confirm results present in the literature and to extend our knowledge of the field by directly applying known forces. I saw that microtubules reoriented in response to compression but not tension. In response to compression, the seedlings increased their growth rate (Robinson et al. 2018). We, thus, were able to demonstrate mechanical stress altering development via reorientation of microtubules.
ACME created a lot of interest from other scientists who have also been looking for better methods to capture quantitative biophysical data at cellular resolution. While it was developed to study Arabidopsis seedlings, the system can be adapted for larger samples and other imaging systems. I will continue to use the method with my SLCU research group to investigate other questions related to plant development, and work with other research groups who find this tool useful.