fos(redirected from Activator protein 1)
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Related to Activator protein 1: Activator Protein 2
FOSA gene on chromosome 14q24.3 that encodes a leucine zipper DNA-binding FOS-type nuclear phosphoprotein, which dimerises with proteins of the JUN family to form the transcription factor complex AP1. FOS proteins regulate cell proliferation, differentiation and transformation, and may be associated with apoptosis.
A family of cancer-causing genes, first identified in viruses, that function within cells as transcription factors. Members of this family can transform normal cells (e.g., fibroblasts) into cancer cells (e.g., osteosarcomas, chondrosarcomas). See: oncogene; transformation
The name is derived from “FBJ osteosarcoma virus, ” in which these oncogenes were first identified.