Dynactin complex (Dynactin)

The Dynactin complex is a large, 23-subunit macromolecular assembly that serves as the primary cofactor for the microtubule-based motor cytoplasmic dynein. It functions as a versatile cargo adapter, linking the dynein motor to a wide array of intracellular loads, including vesicles, organelles, and the mitotic spindle, while simultaneously enhancing the motor's processivity and ability to travel long distances. The complex is structurally organized around a short filament of the actin-related protein Arp1, capped by the pointed-end complex and a sidearm/shoulder domain containing the p150Glued (DCTN1) subunit. [1, 12, 13] Dysfunction of the Dynactin complex is strongly implicated in human disease, particularly neurodegeneration; mutations in the DCTN1 subunit are the primary cause of Perry syndrome and have been linked to amyotrophic lateral sclerosis (ALS) and axonal transport defects in Alzheimer's disease. [9, 11, 20] In the context of drug development, dynactin is a target of interest for anti-cancer therapies that aim to disrupt mitosis and for antiviral strategies, as many viruses hijack this complex to reach the host cell nucleus. [4, 7] While no clinical drugs specifically targeting dynactin are currently approved, experimental small molecules like dynarrestin and HPI-4 are used in research to study its role in transport and cell division. [2, 7]

Other names

Dynein-activating complexp150Glued complexDCTNArp1 filament complexMicrotubule-associated protein complex dynactin

Experimental drugs typically disrupt the interaction between the dynein motor and the dynactin complex or inhibit dynein-driven microtubule gliding by decoupling ATP hydrolysis from motor activity, thereby arresting retrograde transport and mitotic progression.