Background: PTRF (polymerase I and transcript release factor) was first identified as a TTF-I and RNA polymerase I (RNA Pol I) interacting protein that functions in the termination of RNA polymerase I transcription. PTRF has also been described as a protein that localizes to the plasma membrane and caveolae of adipocytes and whose localization is under the control of insulin. In this context, PTRF has been observed to associate with a lipase and have an extranuclear role in the regulation of lipolysis.