FunctionMay play a positive role in AHR-mediated (aromatic hydrocarbon receptor) signaling, possibly by influencing its receptivity for ligand and/or its nuclear targeting. Cellular negative regulator of the hepatitis B virus (HBV) X protein.
Tissue specificityWidely expressed. Higher levels seen in the heart, placenta and skeletal muscle. Not expressed in the liver.
Involvement in diseaseDefects in AIP are a cause of familial isolated pituitary adenoma (FIPA) [MIM:102200]. Defects in AIP are a cause of growth hormone-secreting pituitary adenoma (GHSPA) [MIM:102200]; also known as familial isolated somatotropinomas (FIS) or isolated familial somatotropinoma (IFS) or familial somatotrophinoma or acromegaly due to pituitary adenoma. Defects in AIP are a cause of ACTH-secreting pituitary adenoma (ASPA) [MIM:219090]; also known as pituitary Cushing disease. A pituary adenoma resulting in excessive production of adrenocorticotropic hormone. This leads to hypersecretion of cortisol by the adrenal glands and ACTH-dependent Cushing syndrome. Clinical manifestations of Cushing syndrome include facial and trunkal obesity, abdominal striae, muscular weakness, osteoporosis, arterial hypertension, diabetes. Defects in AIP are a cause of prolactin-secreting pituitary adenoma (PSPA) [MIM:600634]; also known as prolactinoma. Prolactin-secreting pituitary adenoma is the most common type of hormonally active pituitary adenoma.