Mutual transcriptional interference between RelA and androgen receptor

Area of Science:

• Molecular Biology
• Cellular Signaling
• Gene Regulation

Background:

• The androgen receptor (AR) and NF-kappaB signaling pathways are crucial in various cellular processes, including development and disease.
• Interactions between these pathways can significantly impact gene expression and cellular function.

Purpose of the Study:

• To investigate the cross-modulation and potential interference between the androgen receptor (AR) and NF-kappaB/Rel proteins.
• To elucidate the molecular mechanisms underlying the observed interactions between AR and NF-kappaB signaling.

Main Methods:

• Utilized reporter gene assays in COS-1 cells to assess AR and NF-kappaB transactivation.
• Performed transient transfections with varying expression levels of AR, RelA (p65), and NFkappaB1 (p50).
• Conducted protein level analyses, electrophoretic mobility shift assays (EMSA), and protein-protein interaction studies.

Main Results:

• Elevated RelA (p65) expression dose-dependently repressed AR-mediated transactivation, involving the AR N-terminal region.
• AR attenuated RelA transactivation in a dose- and steroid-dependent manner, indicating mutual repression.
• Repression was not due to altered protein levels, DNA binding, or IkappaBalpha induction, suggesting complex formation or coactivator competition.

Conclusions:

• AR and NF-kappaB signaling pathways exhibit mutual transcriptional interference.
• The interaction likely involves the formation of AR-RelA complexes or competition for essential coactivators.
• These findings highlight a novel regulatory mechanism influencing cellular responses to androgens and inflammatory signals.