Heat shock proteins (HSP) are expressed in response to various biological stresses, including high temperatures. There are several major families of HSPs including HSP70, HSP90 and HSP100. The HSP100 proteins generally have amino acid sequences of about 900 residues and contain two nucleotide-binding sites. Within the HSP100 family of proteins, yeast express a ~104 kDa form which is necessary to protect cells from various stress conditions such as heat, heavy metals and ethanol, though mutation studies have shown that the protein is not required for normal growth. Yeast HSP104 has been shown to be a ClpB protein with significant sequence homology to E. coli ClpB, particularly in the two nucleotide-binding sites.
chaperone ATPase HSP104; Heat shock protein 104; HS104; Protein aggregation-remodeling factor HSP104