Overview Cell Structures Cell Migration Cell Division  

Contraction-Dependent Constraint of Cell Shape on Ring-Shaped Substrates

Mader et al., Soft Matter 3:357-363 (2007)

Cultured cells generally maintain a compact shape. However it is unclear if this is constrained only by the membrane/volume relationship, or possibly by an active mechanism. To address the question, 3T3 fibroblasts were plated on micropatterned, ring-shaped adhesive substrates.

Inability of Cells on Ring Substrates to Span More Than 90 Degrees

Despite the ability of 3T3 cells to spread over a much larger area on un-patterned surfaces, on ring-shaped substrates cells are unable to cover more than 90 degrees. Some cells manage to cross the central area and reach a larger spread area. Recording time, 690 min.

 

Ability of Cells to Follow a Ring Geometry upon the Inhibition of Myosin II

Upon treatment with blebbistatin, a potent inhibitor of myosin II, 3T3 fibroblasts start to develop a slender morphology that extends over much of the ring surface, suggesting that myosin II dependent contractile forces are responsible for maintaining a compact shape, similar to the constraint of liquid shape by surface tension (upper video, recording time, 480 min). Inhibition of Rho-dependent kinase, which activates myosin II, induces a similar effect (lower video, recording time, 210 min).