Lamellipodeja
Lamellipodeja is a term that refers to the broad, flattened, sheet-like extensions of the cell membrane that are characteristic of the leading edge of certain motile cells, particularly fibroblasts and amoeboid cells. These structures are dynamic and are crucial for cell migration, adhesion, and engulfment of particles. The formation and retraction of lamellipodia are driven by the regulated assembly and disassembly of actin filaments within the cell cortex. Actin polymerization at the leading edge, often nucleated by the Arp2/3 complex, pushes the cell membrane forward, creating the lamellipodium. Myosin motors then play a role in the retraction of the rear of the lamellipodium, allowing for forward movement. Lamellipodia are also involved in sensing the extracellular environment through the presence of various receptors on their surface. Their characteristic shape and dynamic behavior are essential for processes such as wound healing, immune responses, and embryonic development. The study of lamellipodia has provided significant insights into the fundamental mechanisms of cell motility.