Heat shock-related 70 kDa protein 2 is a protein encoded by the HSPA2 gene.it has a single open reading frame of 1,917 basepairs that encodes a 639-amino acid protein with a predicted molecular mass of 70,030 Da. Analysis of the sequence indicated that HSPA2 is the human homolog of the murine Hsp70-2 gene, with 91.7% identity in the nucleotide coding sequence and 98.2% in the corresponding amino acid sequence. HSPA2 has less amino acid homology to the other members of the human HSP70 gene family. HSPA2 is constitutively expressed in most tissues, with very high levels in testis and skeletal muscle.HSPA2 is expressed abundantly in muscle, heart, esophagus, and brain, and to a lesser extent in testis. A small amount of HSPA2 was detected in breast, stomach, prostate, colon, liver, ovary, and epididymis.