Cloning and expression of Jo-1 protein in E.coli

A vector expressing human histidyl-tRNA synthetase(Jo-1) protein in E.coli was constructed.The full-length DNA fragment encoding Jo-1 protein was obtained by RT-PCR from human placenta tissue.The Jo-1 fragment was cloned into plasmid pMAL-c(a maltose-binding protein,MBP fusion vector) and expressed in E.coli.Western-blotting showed that the fusion protein could react with anti-MBP antibody and anti-Jo-1 antibodies of patients serum,but not with normal serum.Jo-1 protein has immune specificity.