Folliculin-interacting protein 1 (FNIP1)

Acts as a co-chaperone of HSP90AA1.

Inhibits the ATPase activity of HSP90AA1 leading to decrease in its chaperone activity.

Facilitates the binding of customer protein FLCN to HSP90AA1. Competes with the tripping co-chaperone AHSA1 for binding to HSP90AA1, thereby providing a reciprocal regulatory mechanism for chaperoning of client proteins (PubMed:27353360).