Final answer:
The actin-myosin interactions needed for cell migration are located in the cell's rear, with myosin II motors in the cell center generating contractile forces. These interactions function like a stretched spring, allowing the cell to move forward.
Step-by-step explanation:
During cell migration, the actin cytoskeleton plays a pivotal role in forming and extending protrusions at the front of the cell, known as lamellipodia and filopodia, which help in cell movement. Meanwhile, at the rear of the cell, there is a region called the trailing edge or the rear end, where actin-myosin interactions generate contractile forces.
Myosin, a molecular motor protein, interacts with actin filaments in a process involving ATP hydrolysis. The myosin pulls on the actin filaments, creating tension and contractile forces that help propel the cell forward. This rearward contraction assists in pulling the cell body and retracts the trailing edge, facilitating the movement of the cell.
Additionally, molecular complexes like stress fibers and focal adhesions, where actin-myosin interactions occur, contribute to cell traction and generate contractile forces essential for cell migration. These interactions and contractile forces primarily take place at the rear of the cell to facilitate its movement in a specific direction.