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Updated: Oct 7, 2025
11:27
Analysis of SCAP N-glycosylation and Trafficking in Human Cells
Published on: November 8, 2016
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Structural advances in sterol-sensing domain-containing proteins.
Xuelan Wu1, Renhong Yan2, Pingping Cao3
1Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.
Trends in Biochemical Sciences
|January 11, 2022
Summary
The sterol-sensing domain (SSD) in proteins is crucial for cholesterol regulation. Recent studies reveal conserved structures, leading to a proposed classification of SSD proteins into
Area of Science:
- Biochemistry
- Molecular Biology
- Structural Biology
Background:
- The sterol-sensing domain (SSD) is a conserved motif in membrane proteins involved in cholesterol metabolism, transport, and signaling.
- Proteins like Scap, Patched, and NPC1 contain SSDs essential for their sterol-dependent functions.
Purpose of the Study:
- To summarize recent structural and mechanistic insights into SSD-containing proteins.
- To propose a novel classification of SSD proteins based on their functions.
Main Methods:
- Review of recent structural studies on SSD-containing proteins.
- Analysis of conserved structural features and functional mechanisms.
Main Results:
- Identified a conserved core within SSDs critical for sterol sensing.
- Proposed classification of SSD proteins into 'moderator' (M) and 'transporter' (T) types.
- M proteins regulate sterol metabolism, while T proteins facilitate sterol transport via inner tunnels.
Conclusions:
- The conserved core of the SSD is vital for sensing sterol substrates.
- Classifying SSD proteins into M and T types provides a framework for understanding their diverse roles in cholesterol homeostasis.
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