Cover image

Cover Rad23 stabilizes the xeroderma pigmentosum C (XPC) lesion recognition protein after induction of DNA damage. Shown here is an immunofluorescence analysis of intranuclear XPC distribution in murine fibroblast cells, using antibodies directed against XPC (green) and DAPI (blue) to visualize the nuclei. The fibroblasts were derived from embryos containing inactivating mutations in the mammalian homologs of RAD23 (mHR23A and mHR23B), which were corrected by stable transfection of HR23B cDNA. The bright green regions in several of the nuclei represent areas that have been damaged locally by shining UV light through the pores of a filter placed on top of the cells. The damaged nuclei contain more green overall, indicating enhanced stabilization of XPC by the HR23B protein in a DNA-damage-dependent manner. (For details, see Ng et al., 1630.)