Proapoptotic activity of ITM2Bs, a BH3-only protein induced upon IL-2-deprivation which interacts with Bcl-2 Fleischer, Aarne Ayllon Cases, Verónica Dumoutier, Laure Renauld, Jean Christophe Rebollo, Angelita Growth factor deprivation is a physiological mechanism to induce apoptosis. We used an IL-2-dependent murine T cell line to identify proteins that trigger apoptosis. Here we report the identification, the cloning and characterization of ITM2Bs, a protein induced upon IL-2-deprivation. ITM2Bs, which shares the BH3 domain of Bcl-2 family members, is a cytoplasmic and mitochondrial protein. Expression of ITM2Bs induces apoptosis in IL-2-stimulated cells, but not in IL-4-stimulated cells, while overexpression of the long form of the protein is not able to induce apoptosis. In IL-2-stimulated cells, ITM2Bs interacts with the antiapoptotic protein Bcl-2, and does not interact with the proapoptotic Bad. Mutation of the critical L and D residues within the BH3 domain abolished the ability of ITM2Bs to promote apoptosis. 2025-01-28T13:18:25Z 2025-01-28T13:18:25Z 2002 journal article https://hdl.handle.net/10481/100819 10.1038/sj.onc.1205464 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ embargoed access Attribution-NonCommercial-NoDerivatives 4.0 Internacional Nature