HSP90B1 encodes a member of a family of adenosine triphosphate (ATP) -metabolizing molecular chaperones with roles in stabilizing and folding other proteins. The encoded protein (heat shock protein 90 beta family member 1) is localized to melanosomes and the endoplasmic reticulum. Expression of this protein is associated with a variety of pathogenic states, including tumor formation. There is a microRNA gene located within the 5' exon of this gene. There are pseudogenes for this gene on chromosomes 1 and 15.