SIRT7-dependent deacetylation of NPM promotes p53 stabilization following UV-induced genotoxic stress

p53-dependent ceramide response to genotoxic stress.

Both p53 and ceramide have been implicated in the regulation of growth suppression. p53 has been proposed as the "guardian of the genome" and ceramide has been suggested as a "tumor suppressor lipid. " Both molecules appear to regulate cell cycle arrest, senescence, and apoptosis. In this study, we investigated the relationship between p53 and ceramide. We found that treatment of Molt-4 cells w...

SIRT7-dependent deacetylation of CDK9 activates RNA polymerase II transcription

SIRT7 is an NAD+-dependent protein deacetylase that regulates cell growth and proliferation. Previous studies have shown that SIRT7 is required for RNA polymerase I (Pol I) transcription and pre-rRNA processing. Here, we took a proteomic approach to identify novel molecular targets and characterize the role of SIRT7 in non-nucleolar processes. We show that SIRT7 interacts with numerous proteins...

TPL2-NPM-p53 pathway monitors nucleolar stress

Serving as the cellular factory for the biogenesis of ribosomes (the molecular machines responsible for the decoding of mRNAs to proteins), the nucleolus controls a vast array of physiological processes including cell growth and proliferation. It thus comes as no surprise that inherited and acquired abnormalities in ribosome biogenesis can lead to tumorigenesis and that changes in size and numb...

A novel p53-Cdc7 link induced by genotoxic stress.

Genotoxic stress-induced expression of p53 and apoptosis in leukemic clam hemocytes with cytoplasmically sequestered p53.

In nature, the soft shell clam, Mya arenaria, develops a fatal blood cancer in which a highly conserved homologue for wild-type human p53 protein is rendered nonfunctional by cytoplasmic sequestration. In untreated leukemic clam hemocytes, p53 is complexed throughout the cytoplasm with overexpressed variants for both clam homologues (full-length variant, 1,200-fold and truncated variant, 620-fo...