Claude Robert, PhD

We are interested in understanding the fundamental mechanisms associated with early embryonic development and the application of this knowledge to improve the efficiency of assisted reproductive technologies. In livestock, these technologies are used to disseminate genetics from animals that demonstrate the best performance in the breed to improve the performance of future generations. In addition, we use genomics to characterize the genetic potential of different dairy breeds and even pig breeds in order to improve certain characteristics of economic interest such as fertility, cheese yield or meat quality.

Among the fundamental mechanisms of early development that interest us are several elements associated with ovogenesis. For example, the oocyte (which is the largest cell in the body) grows by mechanisms that are not yet well understood because they are unique in cell biology. For example, in several species of birds, amphibians and large mammals, the first cell divisions take place in the absence of nuclear transcriptional activity. Early blastomeres do not transcribe their genome and protein production is supported by messenger RNAs stored during oogenesis. This storage requires precise management for the stabilization of “dormant” messengers, for their recruitment and even for their destruction since many of these stored mRNAs will never be translated. From an applied point of view, these mechanisms are of interest since the vast majority of embryonic mortality (70%) occurs before the activation period of the embryonic genome.

Our recent work shows that cells around the oocyte send mRNAs along their cellular projections that contact the oocyte. Our hypothesis is that in the absence of its own transcriptional capabilities, the oocyte subcontracts its needs to the cells surrounding it. The advantage of this approach could be that the follicular cells are more closely linked to the endocrine status of the ovary than the oocyte is, thus allowing better synchronization of oocyte quality with the physiological condition of the ovarian follicle.

To study the mechanisms of RNA management, we use a candidate gene approach. We aim to gain insight into a family of proteins: the fragile-X mental retardation related proteins, of which FMR1 is the core member. Although the mechanisms involved are not yet known, FMR1 is currently the main marker of ovarian failure in humans.

Mélodie Desnoyers, BSc
MSc student
melodie.desnoyers.2@ulaval.ca

William Poisson, BSc
PhD student
william.poisson.1@ulaval.ca

Pengmin Wang, MSc
PhD student
Pengmin.wang.1@ulaval.ca

Alexandra Carrier, MSc
PhD student
Alexandra.carrier.5@ulaval.ca

Mathilde Marchais, MSc
PhD student
mathilde.marchais.1@ulaval.ca

Isabelle Gilbert, PhD
Research assistant
Isabelle.gilbert.4@fsaa.ulaval.ca