Les événements du mois
Séminaire
Génomes
Lundi 15 janvier 14:00-15:00 - Annabelle Decottignies - de Duve Institute, Brussels Revisiting cellular immortality in melanoma Résumé : Unlimited replicative potential is one of the hallmarks of cancer cells. In melanoma, hTERT (telomerase reverse transcriptase) is frequently overexpressed because of activating mutations in its promoter, suggesting that telomerase is necessary for melanoma development. We observed, however, that a subset of melanoma metastases and derived cell lines had no telomere maintenance mechanism. Early passages of the latter displayed long telomeres that progressively shortened and fused before cell death. We propose that, during melanoma formation, oncogenic mutations occur in precursor melanocytes with long telomeres, providing cells with sufficient replicative potential, thereby bypassing the need to re-activate telomerase. Our data further support the emerging idea that long telomeres promote melanoma formation. These observations are important when considering anticancer therapies targeting telomerase.
Contact : Laure CRABBE <Laure.CRABBE i2bc.paris-saclay.fr>Lieu : Auditorium - bâtiment 21 - Campus CNRS de Gif-sur-Yvette
Vendredi 26 janvier 14:00-15:00 - Yaser Hashem - Institut Européen de Chimie et de Biologie, INSERM Protein translation initiation in eukaryotes : A jigsaw puzzle that has barely started yielding its picture Résumé : Translation initiation in eukaryotes is a highly regulated and rate-limiting process. It results in the assembly and disassembly of numerous transient and intermediate complexes involving over a dozen initiation factors (eIFs). This process culminates in the accommodation of a start-codon marking the beginning of an open reading frame (ORF) at the appropriate ribosomal site. Here, we present a model of the eukaryotic translation initiation process based on recent structures mainly derived by cryo-EM. In addition, we present new results that highlight some of the structural implications of the kozak sequence on the initiation complex formation. Finally we present some of the species-specific aspects of translation initiation in Kinetoplastids, a group of pathogenic eukaryotic organisms.
Contact : Carmela Giglione <carmela.giglione i2bc.paris-saclay.fr>Lieu : Bibliothèque - bâtiment 34 - Campus CNRS de Gif-sur-Yvette
Biologie Cellulaire
Vendredi 12 janvier 11:00-12:30 - Cyril ZIPFEL - The Sainsbury Laboratory, Norwich, UK, invité par Grégory VERT Regulation of receptor kinase-mediated immune signaling Lieu : Auditorium - bâtiment 21 - Campus de Gif
Vendredi 19 janvier 11:00-12:30 - Andreu CASALI - IRB Barcelona, Spain, invité par Jacques Montagne Secondary tumor formation in Drosophila : a model for metastasis Lieu : Auditorium - bâtiment 21 - campus de Gif-sur-Yvette
cytoskeleton club
Mardi 9 janvier 11:30-12:30 - Audrey Esclatine Cytoskeleton club Résumé : A protein of Epstein-Barr-Virus perturbs mitochondrial dynamics by promoting mitochondrial fission followed by mitophagy
Lieu : Bibliothèque - Bâtiment 34, campus de gif
Soutenance
Biologie Cellulaire
Vendredi 26 janvier 14:00-18:00 - Elsa Demes - Département de Biologie Cellulaire, I2BC Etude in vivo des variations de [NO3-] et de pH dans le compartiment cytosolique de cellules de garde et caractérisation fonctionnelle de deux transporteurs vacuolaires de type CLC chez Arabidopsis thaliana. Lieu : Auditorium I2BC - Bâtiment 21, Campus de Gif-sur-Yvette