FURTHER DEVELOPMENT OF THE LOCUS-CONTROL REGION MURINE ERYTHROLEUKEMIA EXPRESSION SYSTEM - HIGH-LEVEL EXPRESSION AND CHARACTERIZATION OF RECOMBINANT HUMAN CALCITONIN RECEPTOR

In order to demonstrate the potential of the LCR/MEL expression system for the expression of seven-transmembrane helix receptors the human c alcitonin receptor (hCTR) has been cloned and expressed at high levels in this system. Using the newly developed single-step expression vect ors pEV and pNV, stable recombinant MEL cells which express the hCTR a t similar to 6 pmol of receptor/mg of total cell protein (60 pmol/mg o f membrane protein), or 1.9 x 10(6) receptors per cell, have been gene rated. Ligand binding studies have shown that the cloned receptor expr essed in MEL cells has properties which are indistinguishable from tho se of the native receptor in T47D cells. It is suggested that MEL cell s expressing seven-transmembrane helix receptors provide an efficient and readily attainable source of material for ligand binding experimen ts using these receptors. (C) 1995 Academic Press, Inc.