p53 targets chromatin structure alteration to repress alpha-fetoprotein gene expression.

GW8510 Increases Insulin Expression in Pancreatic Alpha Cells through Activation of p53 Transcriptional Activity

BACKGROUND Expression of insulin in terminally differentiated non-beta cell types in the pancreas could be important to treating type-1 diabetes. Previous findings led us to hypothesize involvement of kinase inhibition in induction of insulin expression in pancreatic alpha cells. METHODOLOGY/PRINCIPAL FINDINGS Alpha (αTC1.6) cells and human islets were treated with GW8510 and other small-mole...

Transcription factor interactions and chromatin modifications associated with p53-mediated, developmental repression of the alpha-fetoprotein gene.

We performed chromatin immunoprecipitation (ChIP) analyses of developmentally staged solid tissues isolated from wild-type and p53-null mice to determine specific histone N-terminal modifications, histone-modifying proteins, and transcription factor interactions at the developmental repressor region (-850) and core promoter of the hepatic tumor marker alpha-fetoprotein (AFP) gene. Both repressi...

A Direct Intersection between p53 and Transforming Growth Factor Pathways Targets Chromatin Modification and Transcription Repression of the -Fetoprotein Gene†

The effects of electromagnetic fields on alpha-fetoprotein expression in the amniotic fluid of mouse embryo

Amniotic fluid (AF) is essential for fetal development and maturation during pregnancy. The levels of proteins in AF have been determined in many studies to screen for potential biomarkers of pregnancy-associated abnormalities. Alpha-fetoprotein (AFP) is a major AF and plasma protein produced by the yolk sac and the liver during the fetal period. APF serum concentrations are commonly used for s...

Ring1B compacts chromatin structure and represses gene expression independent of histone ubiquitination.

How polycomb group proteins repress gene expression in vivo is not known. While histone-modifying activities of the polycomb repressive complexes (PRCs) have been studied extensively, in vitro data have suggested a direct activity of the PRC1 complex in compacting chromatin. Here, we investigate higher-order chromatin compaction of polycomb targets in vivo. We show that PRCs are required to mai...