Actin Dynamics in Epithelial Cells

The microtubule network provides structural support throughout the cell and is such that it resists compression, whereas actin microfilaments bear the tension of pulling forces. Actin filaments, when combined with other proteins and structures, become stronger and more specialized to perform various tasks within and between cells. In muscle cells, the motor protein myosin is arranged in a lattice configuration between parallel actin filaments. This array of filaments and proteins allows them to slide past each other, providing the elasticity necessary for muscle contraction. In a cell undergoing mitosis, this same actin-myosin pairing is responsible for the cleavage that eventually separates the cell into two daughter cells. In the digital videos presented above, normal opossum kidney epithelial cells (OK line) are expressing enhanced green fluorescent protein (EGFP) fused to human beta-actin.