Nigel Groome PhD Research Studentship
Cell Biology of Plant reticulons
Supervisor: Prof. Chris Hawes
Eligibility: Applicants require a good Honours degree (2.1 or equivalent) and either have been
educated to degree level through the medium of English or have TOEFL 600 (250) / IELTS 7 or
equivalent. Home, EU and international students are eligible.
Start date: September 2009
Value p.a. £13,000 bursary & fees
Closing Date: 18th June with interviews at the end of June
It is has been shown that the shape of the ER does not depend on its attachment to the
cytoskeleton, indicating that factors within the ER membrane itself may be involved. Indeed, it has
recently been found that membrane proteins called reticulons (RTN) are enriched in tubular ER
and can lead to ER tubule formation in an in vitro assay. Reticulons are ubiquitous in higher
eukaryotes. They contain a signature reticulon homology domain (RHD) which comprises two
large hydrophobic regions, further subdivided into four membrane-spanning segments. Each RHD
transmembrane segment is inserted into the ER membrane at an angle, due to its unusual length.
This ‘W’-shaped conformation is postulated to confer curvature to the ER membrane, but a direct
link between topology, transmembrane domain length and curvature has not yet been established.
Reticulon genes are very abundant in plants, with 21 isoforms reported in the Arabidopsis genome,
compared to 7 isoforms in the moss P. patens and only 4 RTN genes described in the human
genome. This striking diversity is likely to reflect the multifunctional role of the plant ER in higher
plants. However, virtually nothing, is known about plant RTN function with only three
publications in the literature to date. This project will look at the distribution and function of
reticulons and putative interacting proteins in arabidopsis and tobacco using fluorescent protein
constructs and live cell imaging. We will investigate: 1. The effect of reticulon expression on ER
morphology and dynamics. 2. The possible oligomerisation of the proteins and interacting proteins
using fluorescence resonance energy transfer. 3. The topology of reticulons and assessment of
transmembrane domains in the ER membrane using a novel redox sensitive GFP based assay. 4.
The role of reticulons in regulating the change between tubular mitotic membranes and the
cisternal nuclear envelope. 5. The role of reticulons in defining sub-domains within the ER
The project will give the successful candidate training in a range of techniques in molecular
biology, biochemistry and live cell imaging with confocal microscopy.
This project is part of a wider collaborative research programme on plant reticulons between the
Plant Endomembrane Group and the group of Dr Lorenzo Frigerio at Biology, University of
Warwick. The successful candidate will be co-supervised by Dr Imogen Sparkes who works on the
reticulon project at Brookes and Dr Frigerio will act as an external supervisor to the project.
Tolley, N.,, Sparkes, I.A., Hunter, P.A., Christian P. Craddock Nuttall, J., Roberts, L.M, Hawes,
C., Pedrazzini, E., & Frigerio, L. (2008). Over expression of a plant reticulon remodels the lumen
of the cortical endoplasmic reticulum but does not perturb protein transport. Traffic 9, 94-102
Plant Cell Biology at Oxford Brookes
The plant cell biology group at Oxford Brookes is well known for work on the plant endomembrane
system and has published widely on the organisation of the nuclear envelope, endoplasmic
reticulum and Golgi apparatus, specialising in live cell imaging, fluorescent protein expression and
electron microscopy. The laboratories are well equipped for molecular cell biology and the
imaging unit has two Zeiss confocal microscopes, transmission and scanning electron
microscopes which are to be replaced early in 2009 with the purchase of a new tomographic
transmission EM. Preparative equipment includes high pressure freezing, freeze-substitution and
Students with a first degree in a biological subject with experience of cell and molecular biology
are encouraged to apply. Prior knowledge of plant cell biology is not a pre-requisite for the
Details of the group can be found on our website: http://www.brookes.ac.uk/plant_endomembrane
Further information from: Chris Hawes (firstname.lastname@example.org)
To apply for this studentship, please complete the University's Postgraduate Application Form:
Applications should be posted to:
Ms Lucy Boyles,
School of Life Sciences
Oxford Brookes University
Oxford OX3 0BP
Please email Lucy Boyles or telephone +44 (0)1865 483295 with any administrative queries.
N.B. Please note that applications will not be accepted by email.