PTGES3

PTGES3 (Prostaglandin E Synthase 3) is a gene that encodes for a protein also known as p23. This protein functions as a cochaperone of heat shock protein 90 (Hsp90).

Function:

PTGES3/p23 plays a crucial role in stabilizing and regulating the activity of Hsp90. Hsp90 is a molecular chaperone involved in the folding, stabilization, and assembly of numerous client proteins, many of which are critical for cellular signaling, cell cycle regulation, and apoptosis. p23 interacts with Hsp90 in a complex with other cochaperones, influencing Hsp90's ATPase activity and client protein binding. It is thought to help maintain the closed, ATP-bound conformation of Hsp90, which is important for proper chaperone function. p23 appears to enhance the affinity of Hsp90 for its client proteins.

Structure and Interactions:

The PTGES3 protein is a relatively small, highly conserved protein. It lacks any readily identifiable catalytic domains. Its interaction with Hsp90 and other cochaperones is essential for its function.

Clinical Significance:

PTGES3/p23's involvement with Hsp90 makes it relevant in various disease contexts, particularly cancer. Because Hsp90 chaperones many oncogenic proteins, disrupting Hsp90 function is a target for cancer therapy. Understanding the role of cochaperones like p23 in modulating Hsp90 activity is critical for developing effective Hsp90 inhibitors. Overexpression of p23 has been observed in several types of cancer, and altered expression levels may correlate with disease progression and drug resistance. Studies suggest that p23 might also play a role in neurodegenerative diseases and inflammation, although further research is needed to fully elucidate its involvement.