In vivo imaging of phenotype changes in muscle.
Skeletal muscle consists of a variety of specialised fibres, which allow muscles to carry out many different functional tasks. The composition of different fibre types is important for the physiological properties of the muscle in response to a changing environment. The fibres are plastic and can change properties in response to variation in neural signal, loading condition or hormonal signals. The alteration can change the metabolic profile, size and other properties of the muscles. However, it is uncertain how a change in the environment affects different fibre types, and how this again contributes to the overall change in the muscle.
The ability to identify and separate different cell types is important for a wide range of biological and medical studies. This is often very challenging as it relies on limited knowledge of the morphology and specific surface markers on the cell. However recently a new technique known as molecular beacons was developed, which targets specific mRNA transcripts with a fluorescent oligonucleotide making it possible to identify and investigate a cell population (singe cell) based on its gene expression.
In this project, the candidate will combine our group's expertise with in vivo imaging on living animals and molecular beacons to target key transcripts of the fibre over time in order to answer central questions on how the fibres change phenotype over time in different settings such as exercise or disease induced muscle wasting. The in vivo results will be validated with molecular techniques.
Some of the methods you will learn: microscopy, in vivo imaging, histology, real time qPCR, SDS-PAGE and Western blotting.
The project will be performed at the Department of Physiology and Cell Biology in the laboratory of Professor Kristian Gundersen. The candidate will be supervised jointly by Mads Bengtsen and Kristian Gundersen.
If any questions, contact Mads Bengtsen (firstname.lastname@example.org / Kristine Bonnevies hus room 2611).
A) In vivo imaging of a mouse single muscle fibre. B) Molecular beacons consist of an oligonucleotide with a fluorophor which is quenched. B) Binding of the beacon to its complementary target mRNA sequence induces a conformational change which separates the fluorophor from the quencher. C) A cell culture experiment where molecular beacons are used to follow the differentiation of fat-derived stem cells. D) Detection of specific RNA transcripts in single cells using molecular beacons (References: Wile et al. Nature Protoc 2014, Darling et al. Brown University)