Cloning and expression of truncated PTHrP receptor in Escherichia coli

To evaluate the effects of recombinant soluble parathyroid hormone related protein receptor(sPTHrPR), the RNA prepared from renal cell carcinoma was reverse-transcribed and amplified by a polymerase chain reaction(PCR). A 543 base pair fragment corresponding to extracellular domain of PTHrPR was obtained and cloned. Sequencing was performed by the dideoxy chain-termination method. Comparison of the nucleic acid sequence with the published data revealed that only one nucleotide had changed. A high level expression vector referred to as pET-3a/sPTHrPR was constructed. The binding specificity of the expression products was proved by indirect ELISA. Our preliminary experiment also showed that the expression products can block the biological activity of PTHrP.