This gene encodes a subunit of dynactin, a component of the cytoplasmic dynein motor machinery involved in minus-end-directed transport. The encoded protein is a component of the pointed-end subcomplex and is thought to bind membranous cargo. A pseudogene of this gene is located on the long arm of chromosome 1. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Jan 2011]