Chicken thyroid hormone receptor alpha requires the N-terminal amino acids for exclusive nuclear localization

The subcellular localization of natural and engineered forms of the chicken thyroid hormone receptor (cTR alpha) is dependent on amino acids encoded in the N-terminal region, The full length receptor protein, cTR alpha-p46, mas found to localize exclusively to the nucleus, whereas the N-terminally shorter variant, cTR alpha-p40, localizes to both the nucleus and the cytoplasm, The exclusive nuclear localization of cTR alpha-p46 is dependent on the presence of the first 11 N-terminal amino acids, but independent of the phosphorylation of the serine at position re. Our data identify a novel role for an N-terminal domain of the full length thyroid hormone receptor. (C) 1997 Federation of European Biochemical Societies.