Arp23dominated

Arp23dominated is a term that describes a cellular state where the Arp2/3 complex plays a significantly dominant role in actin filament nucleation and organization. The Arp2/3 complex is a crucial protein machine that initiates the formation of new actin filaments, particularly branched networks. Its activity is tightly regulated by various factors, including small GTPases like Cdc42 and nucleation-promoting factors (NPFs) such as the WAVE and N-WASP proteins.

In a cellular context described as Arp23dominated, the Arp2/3 complex is highly active, leading to extensive branching and crosslinking of actin filaments. This can result in the formation of dense, mesh-like actin structures that are essential for processes such as cell migration, lamellipodia formation, and endocytosis. The dominance of Arp2/3 activity implies that other actin nucleators, like formins, might be less active or their contributions are overshadowed.

Conditions or cellular signaling pathways that promote Arp23dominated states often involve the activation of specific NPFs. For example, the activation of the WAVE regulatory complex, which in turn activates Arp2/3, is a key driver of lamellipodia protrusion, a process characterized by strong Arp2/3-mediated actin polymerization. The balance between Arp2/3 complex activity and other actin regulators is critical for maintaining cellular shape, enabling movement, and carrying out diverse cellular functions. Dysregulation of Arp2/3 complex activity, and therefore the Arp23dominated state, has been implicated in various diseases, including cancer, where uncontrolled cell migration is a hallmark.