Cellular integrated stress response (ISR), the mitochondrial unfolded protein response (UPRmt), and IFN signaling are associated with viral infections. Activating transcription factor 4 (ATF4) plays a pivotal role in these pathways and controls the expression of many genes involved in redox processes, amino acid metabolism, protein misfolding, autophagy, and apoptosis. The precise role of ATF4 during viral infection is unclear and depends on cell hosts, viral agents, and models. Furthermore, ATF4 signaling can be hijacked by pathogens to favor viral infection and replication. In this review, we summarize the ATF4-mediated signaling pathways in response to viral infections, focusing on human immunodeficiency virus 1 (HIV-1). We examine the consequences of ATF4 activation for HIV-1 replication and reactivation. The role of ATF4 in autophagy and apoptosis is explored as in the context of HIV-1 infection programmed cell deaths contribute to the depletion of CD4 T cells. Furthermore, ATF4 can also participate in the establishment of innate and adaptive immunity that is essential for the host to control viral infections. We finally discuss the putative role of the ATF4 paralogue, named ATF5, in HIV-1 infection. This review underlines the role of ATF4 at the crossroads of multiple processes reflecting host–pathogen interactions.

Le cancer du rein (Renal Cell Carcinoma, RCC) est le 6ème cancer le plus fréquent chez l’adulte en France. Les RCC familiaux ne constituent que 5% des cas, mais leur étude a permis de mieux comprendre la carcinogenèse rénale et de développer de nouvelles thérapies. A ce jour, une dizaine de gènes de prédisposition aux RCC a été identifiée. Or, pour certaines familles, le gène en cause n’a pas été identifié. Mon projet consistait donc à rechercher des nouveaux gènes de prédisposition par l’analyse de séquençage d’exomes chez 13 de ces familles. J’ai détecté des mutations dans plusieurs gènes candidats et me suis focalisée sur la caractérisation du gène NBR1 (Next to BRCA1). Il code un récepteur cargo de l’autophagie qui participe au renouvellement des composants cellulaires. Les études menées suggèrent que la mutation identifiée dans NBR1 peut altérer son rôle dans l’autophagie. Cependant, des analyses complémentaires sont nécessaires afin d’évaluer s’il s’agit d’un nouveau gène de prédisposition aux RCC.

Cellular Integrated Stress Response (ISR), the mitochondrial Unfolded Protein Response (UP-Rmt) and the IFN signaling are associated with viral infections. The Activating transcription fac-tor 4 (ATF4) plays a pivotal role in these pathways and controls the expression of many genes involved in redox processes, amino acid metabolism, protein misfolding, autophagy and apop-tosis. The precise role of ATF4 during viral infection is unclear and depends on cell hosts, viral agents and models. Furthermore, ATF4 signaling can be hijacked by pathogens to favor viral in-fection and replication. In this review, we summarize the ATF4-mediated signaling pathways in response to viral infections, focusing on human immunodeficiency virus (HIV). We examine the consequences of ATF4 activation for HIV replication and reactivation. The role of ATF4 in au-tophagy and apoptosis is explored as in the context of HIV infection programmed cell deaths contribute to the depletion of CD4 T cells. Furthermore, ATF4 can also participate in the estab-lishment of innate and adaptive immunity that are essential for the host to control viral infec-tions. We finally discuss the putative role of the ATF4 paralogue, named ATF5, in HIV infection. This review underlines the role of ATF4 at the crossroads of multiple processes reflecting host-pathogen interactions.