The Lipocalin Apolipoprotein D Functional Portrait: A Systematic Review

Area of Science:

• Biochemistry
• Molecular Biology
• Genetics

Background:

• Apolipoprotein D (ApoD) is a Lipocalin family member with roles in diverse diseases like neurodegeneration and breast cancer.
• Its presence in multiple tissues and subcellular locations suggests complex physiological functions, potentially as a moonlighting protein.

Approach:

• A systematic review of primary publications investigating ApoD properties in chordates was conducted.
• The study analyzed ApoD's ligand-binding and antioxidant activities within its Lipocalin pocket.

Key Points:

• ApoD's function is better described as lipid management rather than long-range lipid transport.
• Its antioxidant activity at the pocket rim influences lipid structures.
• ApoD modulates diverse physiological processes by controlling the redox state of lipid structures.

Conclusions:

• ApoD's combined ligand-binding and antioxidant properties explain its association with lipid structures.
• This mechanism accounts for ApoD's involvement in various cellular compartments, tissues, and disease states.
• Understanding ApoD's lipid management and antioxidant roles offers new perspectives on its physiological significance and future research directions.