Abstract: SET protein is expressed in many tissues and cells, including central nervous system, steroidogenesis cells of adrenal gland and gonads (testis and ovary). SET protein is an intracellular factor with multiple functions, involved in those biological processes such as cell cycle, apoptosis, DNA replication, transcription, epigenetic regulation, oncogenesis and metastasis by many signal pathways. It was newly found that SET protein played a role in regulating androgen production in testis and ovary. SET protein down-regulated the activity of PP2A (did not affect the expression of PP2A), and up-regulated the expressions of CYP17A1 and HSD3β2, which promoted steroidogenesis in gonads. Many regulators of SET protein, such as CKⅡ and hnRNPA2, participated in the pathways of SET protein. CKⅡ enhances the inhibition of SET protein to PP2A activity by inducing phosphorylation of SET protein, while hnRNPA2 plays same role by the combination between its RNP1 sequence and SET protein.

Key words: Androgens, Stromal cells, Protein phosphatase 2, Cholesterol 17 alpha-hydroxylase/17, 20-lyase, SET protein