Geometric control of vimentin intermediate filaments

Area of Science:

• Cell Biology
• Cytoskeleton Dynamics
• Biophysics

Background:

• Vimentin intermediate filaments (VIF) are crucial for cell motility, shape, and adhesion.
• Interactions between VIF, microfilaments (MF), and microtubules (MT) are complex and vital for cellular functions.

Purpose of the Study:

• To investigate the distinct regulatory mechanisms of VIF and MF in response to defined cell shapes.
• To elucidate the role of VIF in maintaining cell polarity and microtubule organization.

Main Methods:

• Utilizing micropatterned substrates to precisely control fibroblast cell morphology.
• Analyzing cytoskeletal organization (VIF, MF, MT) in cells of varying shapes, including vimentin-null cells.

Main Results:

• VIF distribution is globally controlled and shape-independent, unlike MF, which are sensitive to substrate curvature.
• In polarized cells, VIF avoid sharp edges where MF accumulate.
• Vimentin absence in mouse embryonic fibroblasts (MEFs) leads to altered microtubule organization and perturbed cell polarity.

Conclusions:

• VIF exhibit global regulation distinct from the curvature-dependent MF organization.
• VIF play a critical role in establishing and maintaining cell polarity and microtubule organization.
• Micropatterned substrates are effective tools for quantitative analysis of cytoskeleton dynamics.