1. Actin: Actin filaments form a ring-like structure called the contractile ring just beneath the plasma membrane at the site of cell division. This ring is essential for the constriction of the furrow.
2. Myosin II: Myosin II is a motor protein that interacts with actin filaments. It acts as a molecular "rope" that pulls the actin filaments together, causing the contractile ring to shrink and constrict the furrow.
Other proteins also play roles in cytokinesis, such as:
* Profilin: Helps in the assembly of actin filaments.
* Capping proteins: Prevent the ends of actin filaments from being added to or removed from.
* Rho GTPases: Regulate the assembly and disassembly of the contractile ring.
However, actin and myosin II are the key players in generating the force required to divide the cell in two.
