Reptin physically interacts with p65 and represses NF-κB activation.

Area of Science:

• Molecular Biology
• Cellular Biology
• Biochemistry

Background:

• Reptin and Pontin are AAA+ ATPase DNA helicases involved in chromatin remodeling, DNA repair, and transcriptional regulation.
• These proteins participate in various cellular processes, often functioning independently.

Purpose of the Study:

• To identify novel interacting partners of Reptin.
• To elucidate the role of Reptin in the NF-κB signaling pathway.

Main Methods:

• Co-immunoprecipitation to identify interacting partners.
• Reporter gene assays to assess transcriptional activity.
• Western blotting to analyze protein degradation and translocation.

Main Results:

• p65 was identified as a novel interacting partner of Reptin.
• Reptin inhibits NF-κB transactivation following TNFα stimulation.
• Reptin localizes primarily in the cytoplasm and inhibits NF-κB activation by preventing IκB-α degradation and p65 nuclear translocation.

Conclusions:

• Reptin acts as a negative regulator of the NF-κB signaling pathway.
• Cytoplasmic localization of Reptin is crucial for its inhibitory function on NF-κB.
• This study reveals a new mechanism controlling NF-κB pathway activation via Reptin.