The PWWP domain is an essential part of the Hepatoma Derived Growth Factor (HDGF) family of proteins, and is necessary for DNA binding by HDGF [, , ]. This family of endogenous nuclear-targeted mitogens includes HRP (HDGF-related proteins 1, 2, 3, 4, or HRP1, HRP2, HRP3, HRP4, respectively) and lens epithelium-derived growth factor, LEDGF []. Members of the HDGF family have been linked to human diseases, and HDGF is a prognostic factor in several types of cancer [].The PWWP domain, named for a conserved Pro-Trp-Trp-Pro motif, is a small domain consisting of 100-150 amino acids. The PWWP domain is found in numerous proteins that are involved in cell division, growth and differentiation. Most PWWP-domain proteins seem to be nuclear, often DNA-binding, proteins that function as transcription factors regulating a variety of developmental processes [].
