Research

 

Laboratory of Membrane Biology

Our research focuses on membrane transporters and protein transport through the secretory and endocytic pathways in eukaryotic cells.

Our model systems are the yeast Saccharomyces cerevisiae and HeLa cells.

We are currently working on three topics all related to membrane proteins:

  1. Molecular function of calcium membrane transporters involved in human diseases.
  2. Development of quantitative mass spectrometry techniques adapted to membrane proteins.
  3. Mechanisms of protein transport within endocytic pathway.

1) Role of TMEM165/GDT1 transporter in calcium homeostasis

In our lab we use yeast as a model organism to understand a human disease called CDG (Congenital disorder of Glycosylation). This disease is characterized by a glycosylation defect of the secretory proteins. Some CDG-patients have a mutation in a gene called TMEM165 which is a membrane transporter localized in the Golgi apparatus. We study the yeast ortholog of TMEM165 called GDT1. We have recently demonstrated that TMEM165/GDT1 are calcium transporters. We are developing different strategies to further characterize the molecular function, the regulation and the structure of TMEM165/GDT1.

Key publications :
Demaegd et al. (2013) P. Natl. Acad. Sci. USA, 110, 6859-6864

Colinet et al. (2016) Sci. Rep., 6, 24282; doi: 10.1038/srep24282

Colinet et al. (2017) Cell. Microbiol., doi: 10.1111/cmi.12729

 

    

2) Role of ART adaptors in yeast plasma membrane transporters endocytosis: a proteomic approach

Our lab is also interested in membrane trafficking questions such as endocytosis. We have recently developed an optimized plasma membrane purification procedure and a quantitative gel-free proteomic approach to monitor changes in the yeast plasma membrane proteome in cells exposed to external stress. With this approach, we study the role of the ubiquitin-ligase Rsp5 and the ART adaptors in the endocytosis of several transporters such as amino-acid and vitamins transporters.

Key publications :
Szopinska et al. (2011) Moll Cell Proteomics, 10(11) M111.009589

De Block et al (2015) J. Cell Sci., 128(19), 3646-59

Villers et al. (2017) Moll. Cell. Proteomics, 16, 1652-68

    

3) Role BAR-domain proteins in endocytosis in HeLa cells

We have recently adapted our proteomic strategy to human cells to analyze the plasma membrane proteome in HeLa cells. With this approach, we are able to explore the role of different proteins involved in endocytosis. We are particularly interested to understand the role of BAR-domain proteins in clathrin-mediated as well as clathrin-independent endocytosis.