The RNA polymerase III subunit Polr3b is required for the maintenance of small intestinal crypts in mice.

Background & Aims: The continuously self-renewing mammalian intestinal epithelium, with high cellular turnover, depends on adequate protein synthesis for its proliferative capacity. RNA polymerase III activity is closely related to cellular growth and proliferation. Here, we studied the role of Polr3b, a large RNA polymerase III subunit, in the mammalian intestinal epithelium.

The Pioneer Transcription Factor FoxA Maintains an Accessible Nucleosome Configuration at Enhancers for Tissue-Specific Gene Activation.

Nuclear DNA wraps around core histones to form nucleosomes, which restricts the binding of transcription factors to gene regulatory sequences. Pioneer transcription factors can bind DNA sites on nucleosomes and initiate gene regulatory events, often leading to the local opening of chromatin. However, the nucleosomal configuration of open chromatin and the basis for its regulation is unclear.

The transcription factor CREB has no non-redundant functions in hepatic glucose metabolism in mice.

Aims/hypothesis: Excessive hepatic glucose production is a hallmark of insulin resistance in type 2 diabetes. The cAMP responsive transcription factor cAMP responsive element binding protein (CREB), thought to be a key activator of the hepatic gluconeogenic gene regulation programme, has been suggested as a therapeutic target to reduce glucose output by the liver. Here, we test directly the requirement for hepatocytic CREB for the maintenance of glucose homeostasis.