Characterization of PIDD, a death domain-containing p53 target gene.
Published: 2006
Language: eng
Number of pages: 136
ISBN-13: 9780494219188
Description: The p53 tumour suppressor promotes cell cycle arrest or apoptosis in response to diverse stress stimuli. p53-mediated cell death depends in large part on transcriptional upregulation of target genes. One of these targets, p53-induced protein with a death domain (PIDD), was shown to function as a mediator of p53-dependent apoptosis. Previous work in our lab demonstrated that antisense inhibition of PIDD expression attenuated p53-mediated apoptosis suggesting that PIDD expression is required for apoptosis. The work presented here is a characterization of the protein and the apoptotic pathways involved downstream of PIDD. Here we describe the generation and validation of a PIDD polyclonal antibody, and demonstrate its usefulness for Western blotting, immunoprecipitation and immunofluorescence (IF) analysis. These studies demonstrate that PIDD is a cytoplasmic protein and that PIDD is upregulated by p53 activation and in response to DNA damage. In addition, we show that PIDD-induced death and growth suppression in embryonic fibroblasts are dependent on the adaptor protein RAIDD (receptor-interacting protein (RIP)-associated ICH-1/CED-3 homologous protein with a death domain). We also provide evidence that PIDD-induced cell death is associated with the early activation of caspase-2, and later activation of caspase-3 and caspase-7. Our results also show that caspase-2-/-  MEFs in contrast to RAIDD-/- MEFs are only partially resistant to PIDD. These findings suggest that caspase-2 contributes to PIDD-mediated cell death but that it is not the sole effector of this pathway.
Notes: Source: Dissertation Abstracts International, Volume: 68-01, Section: B, page: 0081.

Thesis (Ph.D.)--University of Toronto, 2006.

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