Jo C. Bruusgaard
The cell nucleus can be regarded as the factory of the cell. Both a blueprint (DNA/RNA) and production machinery (ER/Golgi apparatus) are associated with it, and most cells in the body are equipped with one nucleus. Muscle cells are huge on a cellular scale, more than 10 000 times the volume of a large mononucleated cell. Because of their size, muscle cells meet a lot of challenges when it comes to delivering the products (proteins and nucleic acids) to the different parts of the cell. For this reason, muscle cells are multinucleated, and contain thousands of nuclei orderly distributed along the fiber length.
By using a novel in vivo approach to labeling nuclei, we are investigating the number and distribution of myonuclei under varying conditions and at different stages of an animal's life. A dye is injected into the muscle cell (See figure) and the injected cells can be identified after several weeks (inset). Specially engineered software is used to analyze the distribution and cytosolic domain sizes for each nucleus, and how these parameters are changed under various conditions, like denervation, training and ageing.
The neuromuscular synapse
The neuromuscular junction has been widely used for studying the different aspects of synapses in general.There are several reasons for this. The synsapse is large in size and easily accessable, finally it it relatively simple in that only one motor axon innervates one fibre.
A large array of molecules is necessary to form the clusters of Acetylcholine receptors (AChR) and to keep up the structured arrangement of the synapse. One of these proteins is rapsyn, a 43KD protein essential for the formation of the synapse. By overexpressing wild-type and mutant versions we are investigating the function of these proteins on the synapse in living, adult animals.
Cand. scient - 1999, Research at UiO, Kristian Gundersens group.
PhD - 2005 Funded by The Norwegian Research Council, Research at UiO, Kristian Gundersens group.
Post Doc. - 2005 - Funded By UiO (EMBIO), Researh in Antoine Triller's group, Paris, Biologie de la synapse et régulation de la survie neuronale, Ecole Normale Supérierure
Post doc. - 2006-2008 - Funded by The Norwegian Research Council, Research at UiO, Kristian Gundersens group.
Resercher - 2006-2008 - Funded by UiO (EMBIO), Research at UiO, Kristian Gundersens group.
Teacher in Cell biology at Atlantis Medisinske Høgskole
Leader of the Norwegian Physiological Society
Member of the hiring committee for 4 Post doc positions at the department for molecular biosciences
Elected representative for temporary employees in the Board of directors at the Institute for Molecular Biosciences, Univeristy of Oslo
Member of the Board for Scentific Communication, at the Institute for Molecular Biosciences, University of Oslo
Examinator in Cell biology/Physiology at Atlantis Medisinske Høgskole
Elected substitute representative for temporary employees in the Board of directors at the Institute for Molecular Biosciences, University of Oslo
Elected representative for temporary employees in the Board of directors at the Institute for Molecular Biosciences, Univeristy of Oslo.
Secretary in the Norwegian Physiological Society
Leading the lab course w/ lectures for lower grade students at Institute for Biology, University of Oslo
Civil service at The Norwegian Board of Education.
J.C. Bruusgaard, I.B. Johansen, I.M. Egner, Z.A. Rana, and K. Gundersen.
Myonuclei acquired by overload exercise precede hypertrophy and are not lost on detraining.
Proc Natl Acad Sci U S A. 2010 Aug 24;107(34):15111-6. Epub 2010 Aug 16.
Kristian Gundersen and J. C. Bruusgaard
Nuclear domains during muscle atrophy: nuclei lost or paradigm lost?
Journal of Physiology, 586(11):2675–2681, 2008
J.C. Bruusgaard and K. Gundersen
Muscle atrophy is not accompanied by loss of myonuclei
Journal of Clinical Investigation, Apr;118(4):1450-7, 2008
C. Bedet, J. C. Bruusgaard, S. Vergo, L. Groth-Pedersen, S. Eimer, A. Triller, and C. Vannier
Regulation of gephyrin assembly and glycine receptor synaptic stability
Journal of Biological Chemistry, August 1, 2006
J. C. Bruusgaard, K. Liestøl and Kristian Gundersen
Distribution of myonuclei and microtubules in live muscle fibers of young, middle-aged and old mice
Journal of Applied Physiology, 2006 Jun;100(6):2024-30.
J. C. Bruusgaard, A. Brack, S. H. Hughes and Kristian Gundersen
Muscle hypertrophy induced by the Ski protein:cyto-architecture and ultrastructure
Acta Physiol Scand. Oct;185(2):141-9., 2005
J.C. Bruusgaard, K. Liestøl, M. Ekmark, K. Kollstad and K. Gundersen
Number and spatial distribution of nuclei in the muscle fibres of normal mice studied in vivo.
Journal of Physiology 2003 Sep 1;551(Pt 2):467-78.