Testicular receptor 2 (TR2) is a member of the orphan nuclear receptor family. It is widely expressed at a low level throughout the adult testis. TR2 represses transcription and binds DNA directly interacting with HDAC3 and HDAC4 via DNA-binding domains (Franco et al., 2003). TR2 has also been implicated in regulation of estrogen receptor activity in mammary glands (Hun et al., 2002). In addition, TR2 has recently been shown to form a heterodimer with TR4 that can bind to the direct repeat 6 element of the hepatitis B virus (HBV) enhancer II region thus suppressing HBV gene expression (Lin et al., 2008).
