Steroid 5 Alpha Reductase 3 (SRD5a3)

SRD5A3 encodes a steroid 5-alpha-reductase that produces the androgen 5-alpha-dihydrotestosterone (DHT) from testosterone. Mutant SRD5A3 proteins with changes in regions known to affect other SRD5 proteins also abrogated SRD5A3 activity. Knockdown of SRD5A3 expression in an HRPC cell line by siRNA resulted in a significant decrease in DHT production and a marked reduction in cell viability.One gene identified by the screen was confirmed by RT-PCR and Northern blot analyses to be upregulated in HRPC cells but to have little, if any, expression in normal adult organs. The deduced 318-amino acid protein shares sequence similarity and a conserved C-terminal region with steroid 5-alpha-reductases SRD5A1 and SRD5A2, and was designated SRD5A3.