title: Mitochondrial localization of the low level p53 protein in proliferative cells.
abstract: p53 protein plays a central role in suppressing tumorigenesis by inducing cell cycle arrest or apoptosis through transcription-dependent and -independent mechanisms. Emerging publications suggest that following stress, a fraction of p53 translocates to mitochondria to induce cytochrome c release and apoptosis. However, the localization of p53 under unstressed conditions remains largely unexplored. Here we show that p53 is localized at mitochondria in absence of apoptotic stimuli, when cells are proliferating, localization observed in various cell types (rodent and human). This is also supported by acellular assays in which p53 bind strongly to mitochondria isolated from rat liver. Furthermore, the mitochondria subfractionation study and the alkaline treatment of the mitochondrial p53 revealed that the majority of mitochondrial p53 is present in the membranous compartments. Finally, we identified VDAC, a protein of the mitochondrial outer-membrane, as a putative partner of p53 in unstressed/proliferative cells.
authors.affiliation: CNRS UMR, Université de Versailles Saint-Quentin-en-Yvelines, France.
authors.forename: Ioana
authors.initials: I
authors.lastname: Ferecatu
authors.forename: Marie
authors.initials: M
authors.lastname: Bergeaud
authors.forename: Aida
authors.initials: A
authors.lastname: Rodríguez-Enfedaque
authors.forename: Nathalie
authors.initials: N
authors.lastname: Le Floch
authors.forename: Lisa
authors.initials: L
authors.lastname: Oliver
authors.forename: Vincent
authors.initials: V
authors.lastname: Rincheval
authors.forename: Flore
authors.initials: F
authors.lastname: Renaud
authors.forename: François M
authors.initials: FM
authors.lastname: Vallette
authors.forename: Bernard
authors.initials: B
authors.lastname: Mignotte
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Vayssière
mesh_terms: D000818:Animals; D002460:Cell Line; D049109:Cell Proliferation; D006801:Humans; D051379:Mice; D008928:Mitochondria / Q000378:metabolism*; D051381:Rats; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D016159:Tumor Suppressor Protein p53