Résumés disponibles (91) :

SANGARE Lamba Omar (UMR8204-U1019 éq. 01 - Sylviane PIED)
Session :

 

@mail :  lamba-omar.sangare@pasteur-lille.fr      tél. :  0359317431


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Titre de la communication :
Toxoplasma retromer complex is essential for protein maturation, trafficking, biogenesis of secretory organelles and host invasion
Auteurs (et leurs adresses) de la communication :
Lamba Omar Sangaré1,Pierre-Julien Sloves1,Thomas Mouveaux1,Joelle Duflot1,Tchilabalo Dilezitoko Alayi2,Agnès Hovasse2,Westermann Benoît2,Christine Schaeffer-Reiss2,Alain Van Dorsselaer2 and Stanislas Tomavo1 1CIIL IPL Lille 2LBOMS IPHC Strasbourg
Résumé de la communication :
The secretion of rhoptry, microneme and dense granule organelles is required for motility and host cell invasion of apicomplexan parasites. We recently identified and characterized a Golgi-endosomal-like type I transmembrane receptor called TgSORTLR (\"Toxoplasma gondii Sortilin-Like Receptor\"), which is essential for the biogenesis of rhoptry and microneme organelles (Sloves et al., Cell Host Microbe, 2012). We demonstrated that the C-terminal cytoplasmic region of TgSORTLR specifically binds to the T. gondii proteins Vps26 and Vps35, components of the retromer complex. In yeast and mammals, the retromer complex is known to play an essential role in the recycling of receptors from plasma membrane to the TGN (Trans-Golgi Network). We now report the conditional knock out of TgVps35 that demonstrates the key roles of the retromer in the biogenesis of rhoptries and micronemes. In addition, the localization of dense granule proteins is also altered in the TgVPS35 mutant, suggesting that the retromer complex is critical for protein transport to dense granules. Furthermore, we constructed the first retromer-trafficking interactomes in T. gondii using knock in parasite strains expressing HA tagged versions of TgVps35 and TgVps26 proteins followed by co-immunoprecipitation (Co-IP) and proteomic analysis. We identified numerous known proteins involved in vesicular trafficking, but also several unknown parasite-specific proteins, suggesting that retromer-associated proteins that have not been described in mammalian cells and yeast may exist in T. gondii and likely in other apicomplexan parasites. In summary, we will describe how an endosomal-like system plays a key role in the biogenesis of secretory organelles that are essential for host invasion and infection by T. gondii.

SANGARE Lamba Omar (UMR8204-U1019 éq. 01 - Sylviane PIED)