Differential regulation of testosterone vs. 5alpha-dihydrotestosterone by selective androgen response elements

Area of Science:

• Endocrinology
• Molecular Biology
• Genetics

Background:

• Testosterone (T) and 5alpha-dihydrotestosterone (DHT) are key physiological androgens.
• Both androgens activate the androgen receptor (AR) to regulate gene transcription.
• The molecular basis for distinct genomic outcomes mediated by T and DHT via AR remains unclear.

Purpose of the Study:

• To identify molecular factors responsible for differential androgen action.
• To investigate how distinct androgen response elements (AREs) mediate T vs. DHT effects.

Main Methods:

• Yeast genetic selection was employed to identify novel AREs.
• Androgen receptor (AR) transactivation was assessed in mammalian Chinese hamster ovary (CHO) cells.
• Differential responses to T and DHT were analyzed for identified AREs.

Main Results:

• Two novel types of androgen response elements (AREs) were identified that respond differentially to T and DHT.
• These AREs demonstrated distinct T- vs. DHT-induced AR transactivation in CHO cells.
• The magnitude of AR transactivation varied with ARE copy number and sequence compared to a known ARE.

Conclusions:

• Specific ARE sequences are crucial for mediating differential transcriptional responses to T and DHT.
• This selectivity provides insight into the molecular mechanisms underlying distinct androgen actions.
• The findings highlight the role of AREs in fine-tuning androgen signaling pathways.