*4.6. RNA Extraction, and Gene-Expression Studies*

RNA isolation from adrenal tissue and cultured cells, and subsequent reverse transcription were both performed as previously reported [33]. Real-time PCR was performed in triplicate using TaqMan gene-expression assays (Thermo Scientific) for *CRY1*, *CRY2*, *HSD3B1*, *HSD3B2*, *PER1*, *NR4A2*, and *CYP11B2*. Gene-expression levels were analyzed using the 2−ΔΔ*C*<sup>t</sup> relative quantification method, using 18S RNA or *GAPDH* as endogenous reference genes.
