Jacques J. Tremblay, MSc, PhD, LLB

My research program is at the interface of the endocrinology and cellular and molecular biology. We study the molecular mechanisms of Leydig cell differentiation and function. Leydig cells are testicular cells involved in the production of the steroid hormone testosterone. Inadequate levels of steroid hormones are a cause, or at least an aggravating factor, of many human pathologies such as cancers, PCOS, endometriosis, autoimmune and inflammatory diseases. Understanding how this system works in normal conditions, by studying Leydig cells, will provide essential information that will ultimately lead to better diagnostics and treatments for these problems.
Although different hormones and signalling molecules are involved in the differentiation and function of Leydig cells, the transcription factors downstream of these pathways remain unknown. We have identified various transcription factors, some never before reported in Leydig cells, which are essential regulators of cell differentiation in other tissues. Some are found exclusively in the male gonad, while others are present specifically in the adult population of Leydig cells or are unique markers of Leydig stem cells. In addition, we have demonstrated the presence of the CAMKI kinase in Leydig cells and its involvement in gene expression following hormonal stimulation. Finally, we have identified the AMPK kinase as the first molecular brake of steroidogenesis, which has many clinical implications. The targets of these two kinases remain to be identified. Our work on the characterization of the role of these transcription factors and kinases involves classical molecular and cellular biology approaches, as well as gene editing, animal models and proteomic, genomic and bioinformatics.

Laurie Boudreau
MSc student
laurie.boudreau.3@ulaval.ca

Shirley Chazot, BSc
MSc student
shirley.chazot.1@ulaval.ca

Zoheir Demmouche, MSc
PhD student
zoheir.demmouche.1@ulaval.ca

Kenley Joule Pierre, BSc
PhD student
kenley-joule.pierre.1@ulaval.ca

Karine de Mattos, MSc
PhD student
karine.mattos.1@ulaval.ca

Nicholas M. Robert, PhD
Research assistant
Nicholas.Robert@crchudequebec.ulaval.ca