The heat shock proteins (HSPs) are a highly conserved family of stress response proteins. HSPs function primarily as molecular chaperones, facilitating the folding of other cellular proteins, preventing protein aggregation, or targeting improperly folded proteins to specific degradative pathways. Heat Shock Proteins are ubiquitously expressed in all organisms. They are induced in response to various types of environmental stresses like heat, cold, and oxygen deprivation. Heat shock protein H1 (HSPH1, also known as HSP105 and HSP110), exists as three isoforms. HSPH1alpha is 858aa in length and is constitutively expressed. HSPH1beta is 814aa and is induced by heat shock or cell stress. HSPH1 isoform 3 is 817aa and has not been experimentally confirmed. The HSPH1 isoforms have calculated molecular weights of 92-96kD but run at an apparent molecular weight of 105-110kD in SDS-PAGE. HSPH1 acts as a chaperone to prevent thermal aggregation in mammalian cells. Over aa human 388-505, human HSPH1 has 98% and 96% identity to mouse and rat HSPH1, respectively.