IDENTIFICATION AND CHARACTERIZATION OF A NOVEL HSC70-LIKE GENE IN THEHUMAN LUNG-TUMOR CELL-LINE HS24

We determined the cDNA sequence and analyzed the genomic structure of a novel human gene designated HS24/p52, which shows significant simila rity to the ATP-binding domain of stress-70 proteins in the human lung tumor cell line HS24, The 2,203-nucleotide-long cDNA sequence is divi ded into an incomplete 10-nucleotide 5' nontranslated region, a 1,425- nucleotide open reading frame which codes for 474 amino acids and a 76 8-nucleotide 3' nontranslated region, The first 404 of the deduced 474 amino acids resemble the aminoterminal regions of Hsp70 proteins from different species. Furthermore, single amino acid and short amino aci d stretches, which are thought to be essential for the ATPase mechanis m and ATP-binding activity in Hsp70 proteins, are conserved in this se quence, too, The carboxy-terminal 70 amino acids exhibit no significan t similarity to hsp70 nor to any other known protein sequences. The HS 24/p52 gene contains at least five introns, which differ significantly from hsc70 genes with regard to their size and location within the co ding sequences, The total size of this gene is more than 15 kbp, Polym erase chain reaction (PCR) experiments showed that this gene is expres sed in different human cell lines and tissues and it also seems to be highly conserved between human and mouse.