NUPR1L, A NEW P53-TARGET GENE WHICH NEGATIVELY REGULATES THE PROTUMORAL FACTOR NUPR1

MARIA BELEN LOPEZ-MILLIAN; GARCIA MARIA NOE; GRASSO DANIEL; MOLEJON MARIA INES; NEIRA JUAN LUIS; IOVANNA JUAN LUCIO

Granada

Congreso; XXXVII Congress of the Spanish Society of Physiological Sciences (SECF); 2014

Sociedad Española de Ciencias Fisiológicas (SECF)

Nupr1 is a stress protein with nuclear localization. This protein is highly expressed in pancreatic ductal adenocarcinoma and our lab has revealed an essential protumoral role. We have identified by database analysis a sequence with a 57% homology with Nupr1 which we named Nupr1L. Our aim was to study the role of this novel protein as well as the possible interaction with Nupr1. The transcript and the promoter region of Nupr1L human gene were amplified and cloned using PCR-based strategies. Nuclear localization was determinate by IF of the Flagtagged Nupr1L. mRNA expression was measured by RTqPCR. The transactivation activity of the promoter was evaluated by a reporter assay system. The viability and cell cycle assays were carried on by standard methods. According to the primary structure analysis, Nupr1L is localized on the euchromatin. Its transcript is overexpressed in response to metabolic stress. We have found and validated by site-directed mutagenesis the activity of two p53-binding sites in the promoter region. Nupr1L expression induces cell cycle arrest and a concomitant down regulation of it sequence-related Nupr1 protumoral gene. Effect on cell cycle is reversed by overexpressing Nupr1 indicating that Nupr1L effects are mediated at least in part through its effect on Nupr1 expression.Nupr1L could be a new antitumor gene regulated by p53 and regulating it target gene Nupr1.