HSPC300 (hematopoietic stem cell protein 300) is also known as probable protein BRICK1 or C3orf10 (chromosome 3 open reading frame 10) and is a 75 amino acid protein that is expressed as two isoforms and localizes to both the cytoplasm and the cytoskeleton. HSPC300 is thought to regulate cytoskeletal organization and Actin polymerization. Free HSPC300 exists as homotrimers prior to its incorporation into the WAVE complex. The WAVE complex includes five proteins, one of which is HSPC300, that regulate the ARC (Arp2/3 complex) which is responsible for Actin nucleation and is Rac 1-dependent. Because HSPC300 is a highly conserved subunit of the WAVE complex across many species, it is thought to have the same or similar functions in many different organisms.