Translocator protein and steroidogenesis

Two interesting papers by Barren et al. and Owen et al. have been very recently published in Biochemical Journal, reporting the role of translocator protein (TSPO) in steroidogenesis. The involvement of TSPO in the steroid biosynthesis has been suggested by 30 years of researches, using biochemical, pharmacological and genetic experimental approaches. In the last 3 years, however, the TSPO involvement in steroidogenesis has been intensively and profoundly discussed. Using in vivo genetic manipulations aimed at deleting TSPO, some researchers have excluded its role in steroid production. Other research groups, using similar genetic manipulation techniques, have presented different results, corroborating the role of TSPO in steroidogenesis, in particular, when hormonal stimulation occurs. In this scenario, the publications by Barron et al. about 'Steroidogenic abnormalities in translocator protein knockout mice and significance in the aging male' and by Owen et al. about 'TSPO mutations in rats and a human polymorphism impair the rate of steroid synthesis' are part of this debate and provide further and more accurate information supporting the importance of TSPO as a steroidogenesis regulator.