Myosin IIA deficient cells migrate efficiently despite reduced traction forces at cell periphery

Area of Science:

• Cell biology
• Biophysics

Background:

• Cell motility is crucial for development and disease.
• Migrating cells typically exert traction forces on the extracellular matrix.
• The role of specific myosin II isoforms in force generation during migration is unclear.

Purpose of the Study:

• To investigate the individual roles of myosin IIA and IIB in cell migration and traction force generation.
• To determine how myosin II isoform depletion affects cellular structures involved in motility.

Main Methods:

• Utilized micron-sized pillar arrays as force sensors.
• Employed short hairpin RNA (shRNA) to specifically deplete myosin IIA and IIB.
• Analyzed cell migration speed and traction force generation.

Main Results:

• Myosin IIA and IIB localized to the leading and trailing edges, respectively.
• Myosin IIA depletion resulted in loss of stress fibers and focal adhesions.
• Myosin IIA-deficient cells migrated faster but generated less traction force compared to wild-type or myosin IIB-deficient cells.

Conclusions:

• Myosin IIA is involved in generating traction forces at the cell periphery.
• Cells can migrate efficiently with reduced peripheral traction forces, highlighting adaptive mechanisms.
• Myosin IIB plays a role in maintaining cellular structures during migration.