16 April 2018

Studies of protein localization using correlative light and electron microscopy (CLEM)


If a typical cell was the size of Copenhagen then a typical protein would be about the size of a human being. It goes without saying that localization, i.e. where the proteins are located, is therefore an important parameter when you want to understand their function.

In this project, we investigate using advanced microscopy where proteins reside in muscle under different conditions. Studying localization in the anatomically packed skeletal muscle cell is a challenge. Therefore, in collaboration with a microscopic expert from the University of Bristol, we use a microscopy technique called correlative light and electron microscopy (CLEM) in combination with a new method for the production and preservation of muscle cryosections. This enables us to characterize the amount of a given protein of interest in different subcellular areas of the muscle under different conditions.

We test, among other things, whether a previous exercise bout increases the ability to recruit glucose transporter 4 (GLUT4) to the muscle fiber surface membrane to increase glucose uptake in mice and humans by redistributing GLUT4 within the endomembrane-compartments in the hours after work.

If this theory holds true, it will be a conceptual breakthrough in our understanding of how physical activity transiently potentiates insulin's ability to increase glucose uptake.

Financed by

Novo Nordisk Foundation and the Danish Diabetes Academy.


Jonas R. Knudsen JRKnudsen@nexs.ku.dk
Thomas E. Jensen TEJensen@nexs.ku.dk