Functional Studies On The Protein Encoded By Esophageal Cancer Related Gene2 (ECRG2)

A novel tumor suppressor gene, esophageal cancer related gene2 (ECRG2), was cloned and identified. The full-length cDNA of ECRG2 gene contains 258 nucleotides of the open reading frame that predicts 85 amino acids. ECRG2 gene is down regulated in the adjacent and cancerous tissues, especially low frequency in esophageal cancer. This work focused on the functional study of ECRG2 gene. Part â… : The structure and function of the protein encoded by ECRG2 gene was primarily predicted by bioinformatics. NCBI Conserved Domain Database and SMART online indicated that ECRG2 gene contains a characteristic secondary structure of a KAZAL-type conserved domain and was a novel member of the KAZAL-type related serine proteinase inhibitor family. The molecular weight of the protein encoded by ECRG2 gene was about 9.2KD.Part â…¡: The coding sequence of ECRG2 was inserted into the pGEX-4T-l vector. GST-ECRG2 protein was produced in BL21, purified by glutathione-sepharose 4B affinity and identified by Western blot. The purified GST-ECRG2 fusion protein did not display any serine proteinase inhibitor activities. Then the coding sequence of ECRG2 was inserted into the eukaryotic expression vector pcDNA6-V5-His-FLAG and expressed in Hek293 cells. The fusion protein was purified by anti-FLAG...