Crystal structure of human GDF11.

Area of Science:

• Biochemistry
• Molecular Biology
• Structural Biology

Background:

• Transforming growth factor-beta (TGF-β) proteins are crucial for cellular signaling, including muscle differentiation.
• Myostatin (growth differentiation factor 8, GDF8) is a well-characterized inhibitor of muscle growth.
• The function of growth differentiation factor 11 (GDF11) remains less understood, despite high sequence identity to myostatin.

Purpose of the Study:

• To elucidate the structural basis for potential differential signaling between GDF11 and myostatin.
• To understand how minor sequence variations influence protein function within the TGF-β family.

Main Methods:

• X-ray crystallography was used to determine the 3D structure of GDF11.
• Comparative structural analysis was performed between GDF11 and other TGF-β family members, including myostatin.

Main Results:

• The canonical TGF-β domain fold is conserved across family members.
• The crystal structure of GDF11 was resolved to 1.50 Å.
• Structural comparison identified differences between GDF11 and myostatin localized at critical receptor and inhibitor interaction interfaces.

Conclusions:

• The structural differences between GDF11 and myostatin suggest distinct biological functions.
• These findings provide a foundation for understanding the specific roles of GDF11 in cellular processes.