Heat Shock Protein Beta 3 (HSPb3)

Small heat-shock proteins are characterized by a conserved sequence of 80 to 100 amino acids, often called the alpha-crystallin domain, and range in size from 12 to 43 kD in the monomeric state; as multimeric complexes, they range from 150 to 800 kD.

By partial sequencing of cDNA clones and sequence database searching, Lam et al. (1996) isolated an adult heart cDNA that encodes a novel small heat-shock protein of 241 amino acids. Because of its high sequence homology with hsp27, they termed the protein heat-shock protein 27-like protein (HSPL27). It contains casein kinase II but not MAP kinase recognition sites. Northern blot analysis revealed expression of a 0.9-kb transcript in smooth muscle only.