Arrestins regulate cell spreading and motility via focal adhesion dynamics

Area of Science:

• Cell Biology
• Molecular Biology
• Biochemistry

Background:

• Focal adhesions (FAs) are critical for cell attachment and motility.
• Timely disassembly of FAs is essential for cell movement.
• Microtubule-dependent targeting and clathrin recruitment are key to FA disassembly.

Purpose of the Study:

• To identify molecular links between microtubules and clathrin in FA disassembly.
• To investigate the role of nonvisual arrestins in regulating focal adhesion dynamics.

Main Methods:

• Analysis of cells lacking nonvisual arrestins.
• Cell spreading assays on fibronectin and poly-d-lysine.
• Nocodazole washout assays to assess microtubule-dependent FA disassembly.
• Assessment of clathrin dynamics near focal adhesions.
• Utilizing arrestin mutants deficient in clathrin binding.

Main Results:

• Cells lacking nonvisual arrestins exhibit excessive spreading, increased adhesion, and reduced motility.
• Absence of arrestins leads to larger and longer-lived FAs, indicating impaired FA turnover.
• Arrestin deficiency renders FAs unresponsive to microtubule dynamics, confirming the necessity of arrestins for microtubule-dependent disassembly.
• Clathrin dynamics near FAs are decreased in arrestin-deficient cells.
• Arrestin mutants unable to bind clathrin fail to rescue the observed phenotype.

Conclusions:

• Nonvisual arrestins act as crucial molecular links between microtubules and clathrin.
• Arrestins are essential regulators of focal adhesion disassembly, controlling FA turnover and cell motility.
• The clathrin-binding capability of arrestins is vital for their function in focal adhesion regulation.