AHRR
Function
Mediates dioxin toxicity and is involved in regulation of cell growth and differentiation. Represses the transcription activity of AHR by competing with this transcription factor for heterodimer formation with the ARNT and subsequently binding to the xenobiotic response element (XRE) sequence present in the promoter regulatory region of variety of genes. Represses CYP1A1 by binding the XRE sequence and recruiting ANKRA2, HDAC4 and/or HDAC5. Autoregulates its expression by associating with its own XRE site.
Tissue Specificity
Highly expressed in testis, lung, ovary, spleen and pancreas. Highly expressed in mononuclear cells (MNCs) from umbilical cord blood. Isoform 3 is highly expressed in lung, kidney, spleen and thymus. Down-regulated malignant tissue from different anatomical origins, including colon, breast, lung, stomach, cervix, and ovary.
Cellular localization
- Cytoplasm
- Nucleus
- Predominantly in the nuclear compartment. First cytoplasmic, translocates into the nuclear compartment upon interaction with ARNT in the cytoplasmic compartment.
Alternative names
BHLHE77, KIAA1234, AHRR, Aryl hydrocarbon receptor repressor, AhR repressor, AhRR, Class E basic helix-loop-helix protein 77, bHLHe77