Project Title: Functional analysis of dystrophin in vivo

Supervisors: Professor Steve Winder (BMS &CMIAD) and Dr Jamie Hobbs (Physics and Astronomy & CMIAD)

Application deadline: Friday 14 December 2012.

Project description:

The dystrophin protein is an essential component of the muscle fibre membrane that protects it from the stresses and strains induced during contraction. Loss of dystrophin function such as in the inherited muscle wasting disease Duchenne muscular dystrophy (DMD), leads to muscle membrane fragility resulting in muscle fibre necrosis and premature death.

Despite a wealth of information and understanding of the genetics underlying the disease, our knowledge of how dystrophin actually functions is still somewhat rudimentary. Recent in silico analyses and biophysical studies have provided evidence for a new model of how dystrophin interacts with and provides support to the muscle membrane. This study aims to extend these findings into a cellular context and to examine in living muscle fibres the contribution of dystrophin and different parts of dystrophin to muscle fibre membrane integrity.

Using muscle fibres generated from mice that lack dystrophin we will replace different dystrophin molecules lacking specific regions in order to assess the functionality of those domains in maintenance of muscle fibre integrity. We will employ confocal fluorescence microscopy to examine the organisation of the fibres and the distribution of these proteins in the muscle fibres, atomic force microscopy to assess the contribution of the different proteins to membrane stiffness, and mechanical loading experiments to determine the effect of the different proteins on cellular signalling responses to stress.

This study will give great insight into the function of the dystrophin protein and provide the student with a range of complimentary skills covering molecular cell biology, cellular imaging,  scanning probe microscopy and biomechanics.

References:

1. Le Rumeur, E., Winder, S.J. and Hubert, J.-F. (2010)
   Dystrophin: More than just the sum of its parts. Biochim.
   Biophys. Acta, 1804, 1713-1722.
2. Le Rumeur, E., Hubert, J.-F. and Winder, S.J. (2012)
   A new twist to coiled coil.
   FEBS Lett., 586, 2717-2722.
3. Sarkis, J., Vié, V., Winder, S.J., Renault, A., Rumeur, E.L. and Hubert, J.-F. (2012)
   Resisting sarcolemmal rupture: Dystrophin repeats increase Membrane-Actin stiffness.
   Faseb J, doi: 10.1096/fj.12-208967.

Contact details:

Professor Steve Winder

Web: http://www.sheffield.ac.uk/bms/research/winder

Email: s.winder@sheffield.ac.uk

Dr Jamie Hobbs

Web: http://www.shef.ac.uk/physics/contacts/jamie-hobbs

Email: jamie.hobbs@sheffield.ac.uk