The barrier function of skin is known to be localized to the stratum corneum, the outermost layer of the skin. The stratum corneum is composed of corneocytes (dead skin cells) surrounded by a dense lipid matrix that serves as the only continuous path for permeation through the skin. As such, understanding the structure of this lipid matrix, and the influence of its structure on permeability, is crucial to understanding barrier function. While much is known about the composition of the stratum corneum membrane in healthy skin — e.g., it is composed of roughly equal parts cholesterol, free fatty acids, and a mixture of 12 different ceramides — far less is known about the role of each of the 14 different lipids components in maintaining the barrier function at the molecular level or how anomalies in composition and organization alter barrier function. Molecular simulation provides a means to probe the behaviour of stratum corneum lipid systems at length-scales not accessible to experiment and to develop a molecular level understanding of the membrane behaviour.
This project will involve performing atomistic and coarse-grained molecular dynamics simulations of membrane systems to understand the molecular-level interactions and self-assembly behavior of the lipids, with direct comparisons to be made with experimental measurements of structure and permeability from our collaborators. Example publications that have come out of prior work simulating the SC lipid structure can be found at https://goo.gl/Hvab8Q.
Utilising opensource simulation engines and existing analysis code the student will examine:
- the role of extended conformations of both long and very long ceramides in the organization/structure/interactions of the stratum corneum.
- develop a multiscale approach to identify recognizable signatures indicative of phase separation to allow more precise identification of lamella lipid composition for comparison with experiment.
- synthetic lipid models that closely represent healthy and diseased stratum corneum to compare and contrast in order to determine barrier function. We hypothesize that the chain length of the FFAs and CERs is the key difference that leads to an inferior barrier.
Applicants should have some experience in writing computer codes (such as Python or MATLAB). Applicants need not have prior molecular simulation experience, though familiarity with open-source codes such as GROMACS and HOOMD is an advantage.
For further information please contact Clare McCabe email@example.com
All applicants must have or expect to have a 1st class BSc, MChem, MPhys, MEng, MSci or equivalent degree by 01/04/23 date in order to allow registration to start in May 2023. Selection will be based on academic excellence and research potential, and all short-listed applicants will be interviewed (in person or via Teams).
Closing Date: 31/1/23. All successful candidates must commence studies by 1/5/23
How to Apply
When applying through the Heriot-Watt on-line system please ensure you provide the following information:
(a) in ‘Study Option’
You will need to select ‘Edinburgh’ and ‘Postgraduate Research’. ‘Programme’ presents you with a drop-down menu. Choose Bio-engineering and Bio-sciences PhD for study option
(b) in ‘Research Project Information’
You will be provided with a free text box for details of your research project. Enter Title of the project for which you are applying and also enter the supervisor’s name.
This information will greatly assist us in tracking your application.
For questions about the application process, please contact firstname.lastname@example.org