It is involved in a diverse array of cellular functions, including ER-to-Golgi transport, the centripetal movement of lysosomes and endosomes, spindle formation, chromosome movement, nuclear positioning, and axonogenesis.

It is an actin-related protein, and is approximately 60% identical at the amino acid level to conventional actin.

Highly purified, native Arp1 polymerize rapidly at extremely low concentrations into short filaments in vitro that were similar, but not identical, in length to those in dynactin.

As for conventional actin, Arp1 can bind and hydrolyze ATP, and Arp1 assembly is accompanied by nucleotide hydrolysis.

[12] Arp1 has been shown as the domain for dynactin binding to membrane vesicles (such as Golgi or late endosome) through its association with β-spectrin.