Maryse LEBRUN

Information

Scientific interests and projects

We are interested in the cellular and molecular mechanisms that enable apicomplexan parasites to infect and develop inside their host. The phylum Apicomplexa comprises single-celled eukaryotic parasites. They are important pathogens of humans and domestic animals. It includes Plasmodium spp. the causative agent of malaria, responsible for almost half million human deaths per year. It also includes Toxoplasma, a prominent cause of human congenital infections, and Cryptosporidium, a leading cause of severe diarrhea and mortality in infants. No vaccine currently exists against these parasites.

The objectives of our team are to decipher cellular and molecular features related to two essential parasitic functions: host cell invasion and intracellular replication, with the aim of identifying novel therapeutic strategies. Our research is mainly focused on T. gondii, which is a relevant model for many features conserved throughout the phylum. We then extend our important discoveries to the malaria parasite. We use a broad array of cell biological and biochemical approaches, as well as cutting-edge molecular genetics and genome editing.

The M. Lebrun group explores i) the structure/function of proteins constituting the moving junction, a key structure formed during invasion of the host cell, ii) the mechanisms that trigger rhoptry exocytosis upon binding of the parasite to the host cell, iii) the fusion machinery of the rhoptry with the parasite plasma membrane, and iv) how rhoptry content is introduced in the host.

The group of S. Besteiro focuses on the contribution of an endosymbiotic organelle to the metabolism and survival of T. gondii in the context of both the acute and chronic phases of toxoplasmosis.

The group of M. Lamarque is interested in the functional characterization of selected P. falciparum phosphatases related to the invasion and egress mechanisms.

Top 5 publications of the last 5 years

1. Suarez C, Lentini G, Ramaswamy R, Maynadier M, Aquilini E, Berry-Sterkers L, Cipriano M, Chen AL, Bradley P, Striepen B, Boulanger MJ, Lebrun M. A lipid-binding protein mediates rhoptry discharge and invasion in Plasmodium falciparum and Toxoplasma gondii parasites. (2019). Nature Communications. 10(1):4041. doi: 10.1038/s41467-019-11979-z

2. Guérin A, Corrales RM, Parker ML, Lamarque MH, Jacot D, El Hajj H, Soldati-Favre D, Boulanger MJ, Lebrun M. Efficient invasion by Toxoplasma depends on the subversion of host protein networks. Nature Microbiology, (2017) Oct;2(10):1358-1366. doi: 10.1038/s41564-017-0018-1

3. Nguyen HM, El Hajj H, El Hajj R, Tawil N, Berry L, Lebrun M, Bordat Y, Besteiro S. Toxoplasma gondii autophagy-related protein ATG9 is crucial for the survival of parasites in their host. Cellular Microbiology, (2017) Jun (19) 6. doi: 10.1111/cmi.12712

4. Parker ML, Penarete-Vargas DM, Hamilton PT, Guérin A, Dubey JP, Perlman SJ, Spano F, Lebrun M *, Boulanger MJ*. Dissecting the interface between apicomplexan parasite and host cell: Insights from a divergent AMA-RON2 pair. PNAS, (2016) Jan 12;113(2):398-403. *equal contribution. doi: 10.1073/pnas.1515898113

5. Lévêque MF, Berry L, Cipriano MJ, Nguyen HM, Striepen B, Besteiro S. Autophagy- Related Protein ATG8 Has a Noncanonical Function for Apicoplast Inheritance in Toxoplasma gondii. MBio. (2015) Oct 27;6(6):e01446-15. 10.1128/mBio.01446-15