COMPOSITION, METHODS AND REAGENTS FOR THE SYNTHESIS OF A SOLUBLE FORM OF HUMAN PEX

摘要

This invention relates to a soluble form of PEX, PEX being a type II integral membrane glycoprotein. This enzyme is the gene product of a phosphate regulating gene with homologies to endopeptidases on the X chromosome. To produce a soluble form of PEX, the transmembrane anchor domain has been modified to encode a signal peptidase coding sequence. The soluble PEX therefore comprises the active ectodomain. An inactive mutant of PEX is also an object of this invention. Both soluble and inactive mutant forms of PEX can be used to screen ligands to PEX. These ligands will be used as substrates or inhibitors of PEX. PEX being phosphaturic, an inhibitor thereof will be used to treat phosphaturia and/or hypophosphatemia. On the opposite, a substrate for PEX or PEX itself will be used to treat hyperphosphatemia.