Virology & Mycology
Open Access

Early step of JSRV-mediated cell transformation involves the interaction between Env and the RALBP1 cellular protein

International Conference on Retroviruses & Novel Drugs

June 08-09, 2015 Chicago, USA

Caroline Leroux1, Margaux Monot1, Alexandra Erny1, Barbara Gineys1, Sophie Desloire1, Christine Dolmazon1, Anne Aublin-Gex2, Vincent Lotteau2 and Fabienne Archer1

Posters-Accepted Abstracts: Virol-mycol

Abstract :

Ovine pulmonary adenocarcinoma is a naturally occurring lung cancer in sheep induced by the Jaagsiekte Sheep RetroVirus (JSRV). Its envelope glycoprotein (Env) carries oncogenic properties, and its expression is sufficient to induce in vitro cell transformation and lung adenocarcinoma in vivo. The precocious mechanisms leading to initiation of cell transformation are still unknown, and identification of cellular partners of JSRV envelope remains crucial for deciphering mechanisms leading to cell transformation. We initially identified RALBP1 (Ral A Binding Protein also known as RLIP76 or RIP), a cellular protein implicated in the ras pathway, as a partner of JSRV Env by yeast double-hybrid screening and confirmed formation of RALBP1/ Env complexes in mammalian cells. Expression of the RALBP1 protein was repressed in tumoral lungs as well as in tumorderived alveolar type II cells. Through its inhibition using specific siRNA, we showed that RALBP1 was involved in envelopeinduced cell transformation and in modulation of the mTOR/ p70S6K pathway by the retroviral envelope.