Overview Cell Structures Cell Migration Cell Division  

Dissecting Regional Functions in Cell Migration with Microfluidic Local Drug Delivery

Guo and Wang, Mol. Biol. Cell. 23:1657-1663 (2012)

To understand the mechanism of cell migration, we cultured fibroblasts on micropatterned tracks to induce persistent migration with a highly elongated morphology and well-defined polarity, which allows microfluidic pharmacological manipulations of regional functions, using inhibitors of actin or myosin II. The observations suggest a three-component model of cell migration where a contractile middle section is responsible for the movement of a bulky cell body and the detachment/retraction of a resistive tail, thereby allowing these regions to undergo coordinated movement with a moving anterior region that carries little load.

Distinct Behaviors of Anterior and Posterior Regions during Cell Migration.

An NIH3T3 cell migrates on a surface with micropatterned straight lines. Recording was performed with a motorized stage and a customized program that locks the position of the nucleus.  Note the well defined anterior and posterior regions. Total recording time, 60 min.

Differential Responses of Anterior and Posterior Region to the Inhibition of Myosin II.

Treatment of an NIH3T3 cell globally with 10 microM blebbistatin causes failure of tail retraction, however frontal protrusion and migration of the nucleus are not affected. Note the striking stretching of the posterior region while the anterior region continues to migrate with little change in morphology.  Total recording time, 8 hours.

Lack of Responses to Local Application of Y-27632 in the Anterior Region.

Treatment of an NIH3T3 cell with Rho kinase inhibitor Y-27632 at the leading edge, as indicated by the red fluorescence, has no significant effect on protrusion, tail release, or nuclear translocation. The concentration of Y-27632 released from the needle is 100 microM.  Total recording time, 160 min.

Lack of Responses to Local Application of Blebbistatin in the Tail Region.

Treatment of an NIH3T3 cell with blebbistatin at the leading edge, as indicated by the red fluorescence, has no significant effect on protrusion, tail release, or nuclear translocation. The concentration of blebbistatin released from the needle is 50 microM. Total recording time, 80 min.

Inhibition of Cell Body Translocation without Affecting Frontal Movement by Local Application of Y-27632 in Front of the Nucleus.

Treatment of an NIH3T3 cell with Rho kinase inhibitor Y-27632 just in front of the cell body, as indicated by the red fluorescence, causes strong inhibition of nuclear translocation without affecting frontal movement, which results in striking elongation of the region in front of the nucleus. Tail elongation and retraction is also inhibited. The concentration of Y-27632 released from the needle is 100 microM.  Total recording time, 112 min.

Inhibition of Frontal Extension without Affecting Cell Body Movement by Local Application of Cytochalasin D in the Anterior Region.

Treatment of an NIH3T3 cell with cytochalasin D at the leading edge, as indicated by the red fluorescence, does not affect nuclear translocation or tail retraction but causes strong inhibition of frontal protrusion. The concentration of cytochalasin D released from the needle is 2 microM.  Total recording time, 3 hours. 

Reversal of Nuclear Movement by Local Application of Cytochalasin D in the Posterior Region.

Treatment of an NIH3T3 cell with cytochalasin D in the posterior region, as indicated by the red fluorescence, causes reversal of nuclear movemen. The concentration of cytochalasin D released from the needle is 2 microM. Total recording time, 3 hours.