Continuous Production of Soluble Extracellular Domain of a Type-I Transmembrane Protein in Mammalian Cells Using an Epstein–Barr Virus Ori-P-Based Expression Vector

Purification of membrane proteins is critical for biochemical and functional analyses.Often, purification of a specific domain may be sufficient to dissect molecular mechanisms involved in the biological function of the protein.Recombinant DNA technology offers a simple means of production of specific protein domains.Many eukaryotic and prokaryotic heterologous expression systems have been used to produce proteins in quantities suitable for biochemical analysis.However, a mam-FIG.1. Construction of E-cadherin-Fc fusion protein (Cad-Fc).See text for detail.Only the expression cassettes of the plasmids are malian system is the best choice for production of the shown.Solid blocks denote coding regions.Note that the diagram is extracellular domain of mammalian transmembrane not to scale.Abbreviations: CMV, cytomegalovirus early promoter;proteins, especially when proper posttranslational E-cad (ex), E-cadherin extracellular domain; Fc, CH2-CH3 domain modification of the protein is essential for function.