Patent ID: 8003757

Claim:
A receptor complex comprising: a recombinant receptor polypeptide comprising an extracellular ligand-binding domain derived from a receptor; and a cytoplasmic domain derived from a receptor, wherein at least one activation site of the cytoplasmic domain has been inactivated by either mutation, deletion, or mutation and deletion, the cytoplasmic domain comprising at least two parts: a first part derived from a cytoplasmic domain of a receptor; and a second part comprising a heterologous bait polypeptide which is heterologous to the cytoplasmic domain of the receptor from which the first part is derived; wherein the cytoplasmic domain comprises at least a JAK binding site; and a recombinant prey polypeptide comprising a first polypeptide that interacts with the heterologous bait polypeptide and a second polypeptide comprising at least one activation site; wherein the receptor complex is activated by binding of a ligand to the extracellular ligand-binding domain and by binding of the recombinant prey polypeptide to the heterologous bait polypeptide.