Clathrin senses membrane curvature.

Area of Science:

• Cell Biology
• Biophysics
• Molecular Biology

Background:

• Protein assembly at curved membranes is vital for cellular functions like endocytosis.
• Adaptor proteins recruit clathrin coats to curved membrane regions.
• It was unclear if clathrin itself senses curvature or is passively recruited.

Purpose of the Study:

• To investigate if the clathrin coat actively senses membrane curvature.
• To compare clathrin's curvature sensing ability with adaptor proteins.
• To understand the role of clathrin assembly in curvature detection.

Main Methods:

• Utilized a synthetic tag to induce clathrin assembly directly on membrane surfaces.
• Quantified clathrin's ability to sense and assemble at high membrane curvature.
• Measured the amplification of curvature sensitivity when clathrin is recruited by adaptors.

Main Results:

• Clathrin assembly, not unassembled triskelia, strongly senses membrane curvature.
• Clathrin's curvature sensitivity is comparable to known adaptor proteins.
• Adaptor-mediated recruitment amplifies clathrin's curvature sensitivity 2- to 10-fold.

Conclusions:

• Clathrin acts as a potent sensor of membrane curvature through its assembly process.
• A synergistic relationship between clathrin coat and adaptors enhances precision in membrane traffic.
• Protein networks, not individual domains, are likely key drivers of membrane curvature sensing.