pVHL's kryptonite: E2-EPF UCP

E2-EPF UCP Possesses E3 Ubiquitin Ligase Activity via Its Cysteine 118 Residue

Here, we show that E2-EPF ubiquitin carrier protein (UCP) elongated E3-independent polyubiquitin chains on the lysine residues of von Hippel-Lindau protein (pVHL) and its own lysine residues both in vitro and in vivo. The initiation of the ubiquitin reaction depended on not only Lys11 linkage but also the Lys6, Lys48 and Lys63 residues of ubiquitin, which were involved in polyubiquitin chain fo...

EPF Background Brief: Patient Empowerment

The ubiquitin-conjugating enzyme E2-EPF is overexpressed in primary breast cancer and modulates sensitivity to topoisomerase II inhibition.

We identified the ubiquitin-conjugating enzyme E2-EPF mRNA as differentially expressed in breast tumors relative to normal tissues and performed studies to elucidate its putative role in cancer. We demonstrated that overexpression of E2-EPF protein correlated with estrogen receptor (ER) negativity in breast cancer specimens and that its expression is cell cycle-regulated, suggesting a potential...

UCP-2 and UCP-3 Proteins Are Differentially Regulated in Pancreatic Beta-Cells

BACKGROUND Increased uncoupling protein-2 (UCP-2) expression has been associated with impaired insulin secretion, whereas UCP-3 protein levels are decreased in the skeleton muscle of type-2 diabetic subjects. In the present studies we hypothesize an opposing effect of glucose on the regulation of UCP-2 and UCP-3 in pancreatic islets. METHODOLOGY Dominant negative UCP-2 and wild type UCP-3 ade...

Life without UCP I : mitochondrial , cellular and organismal characteristics of the UCP I - ablated mice

Mice devoid of the original uncoupling protein UCPl have provided opportunities to delineate UCPl function in a series of biochemical and physiological contexts. The isolated brown-fat mitochondria from such mice are fully coupled (without the addition of GDP), but still exhibit a depressed capacity for ATP synthesis. However, they only show a 2-fold decrease in sensitivity to the de-energizing...