Our focus is the pituitary, and we are particularly interested in the differential regulation of the gonadotropins, follicle-stimulating hormone (Fsh) and luteinizing hormone (Lh).
Fish are excellent models for this purpose because they have distinct cell types (gonadotropes) producing either Fsh or Lh. This is in contrast to e.g. mammals that have one cell type producing both hormones.
Our interests cover both basic and applied aspects of fish reproduction. Important questions related to e.g. the pubertal maturation of gonadotrope cells, or the differential regulation of Fsh and Lh are not well understood in any vertebrate. On the applied side, understanding fish reproduction is important both for effective and welfare-oriented aquaculture, and for conservation programs where stocking is often necessary to preserve endangered populations.
In the lab, we combine a wide range of advanced molecular, cellular, and genomics tools in trying to understand basic mechanisms of pituitary physiology. We perform in vitro, ex vivo, in vivo and in silico experiments to utilize the advantages each of these approaches can offer.
For many of our studies we use the Japanese medaka (Oryzias latipes) and take advantage of the suit of molecular and genetic tools this model system can offer. In some projects, we work on other species like Atlantic salmon (Salmo salar), European eel (Anguilla anguilla), and Atlantic cod (Gadus morhua).
Current externally funded projects
IMPRESS, or Improved Production Strategies for Endangered Freshwater Species (H2020-MSCA-ITN 2015-2019). Impress is a multi-disciplinary project devoted to improve the fitness of fish produced for stocking purposes as a means to preserve endangered species. We focus on three species of fish, salmon, eel, and sturgeon, and the project is a collaboration between nine European partner institutions, together educating fifteen PhD students, with NMBU as coordinator.
EvoSize, or Size-dependent anthropogenic perturbations -from genes to ecosystems and back (RCN FriPro 2016-2020). Evosize aims to investigate how anthropogenic size truncation in populations affects ecosystem function and resilience, considering the whole cascade of biological processes from genes to food web and back. Our part in this project, which is a collaboration with the University of Oslo (Asbjørn Vøllestad) and Sorbonne University of Paris (Eric Edeline), involves using a combination of bulk RNA-seq and scRNA-seq to understand how the pituitary, a key organ in the regulation of life history, develops and matures from juvenile to adult stages.
REEF, or Productivity and Resilience Enhancement of Exploited Fish stocks: an experimental Approach (RCN Marinforsk 2016-2020). REEF aims to experimentally investigate if and how a reverse fishing regime, i.e. selective harvest of small individuals, may enhance productivity and resilience of exploited fish stocks. Our part in this project, which also involves the University of Oslo (Asbjørn Vøllestad) and Sorbonne University of Paris (Eric Edeline), focuses on how variation in gene-expression profiles control the evolution of body size in medaka using RNA-seq analyses on key tissues regulating body growth, e.g. brain and pituitary.
DigiBrain: From genes to brain function in health and disease (RCN Digital Life 2016-2020). In DigiBrain, our aim in this inter-disciplinary project is to develop models for intracellular signaling in excitable cells in close collaboration with mathematical modelers. We use endocrine cells from the medaka pituitary for this purpose. The project is coordinated by Marianne Fyhn, University of Oslo.
Transcriptome sequencing of Atlantic salmon pituitary to identify novel genes involved in pubertal activation (RCN Havbruk 2015-2019). The main aim of this project is to identify major qualitative and quantitative changes in pituitary gene expression during puberty in Atlantic salmon using RNA-seq. Collaboration with Anna Wargelius at Institute of Marine Research, Bergen.
Melatonin - Direct effects on gonadotrope cells in the fish pituitary? (RCN Havbruk 2015-2019). Here we aim to investigate if melatonin has direct effects on gonadotrope cells in the pituitary of fish, whether melatonin can modulate effects of Gnrh, and whether effects of melatonin are manifested at the level of ion channel expression in the target cell.