This gene is a member of the J protein family. J proteins function in many cellular processes by regulating the ATPase activity of 70 kDa heat shock proteins. The encoded protein plays a role in membrane trafficking and protein folding, and has been shown to have anti-neurodegenerative properties. The encoded protein is known to play a role in cystic fibrosis and Huntington's disease. A pseudogene of this gene is located on the short arm of chromosome 8.