Expression cloning of a cDNA encoding the murine interleukin 4 receptor based on ligand binding.
Interleukin 4 (IL-4) is a potent mediator of growth and differentiation for various lymphoid and myeloid cells. To isolate a cDNA encoding the murine IL-4 receptor, we have developed an expression cloning method that uses biotinylated ligand as a probe and that may be generally applicable to cloning of receptor genes. COS-7 cells transiently transfected with the cloned full-length cDNA bind murine IL-4 specifically with a Kd = 165 pM. Crosslinking of 125I-labeled IL-4 to COS-7 cells transfected with the cDNA reveals binding to proteins of 120-140 kDa. IL-4-responsive cells also express IL-4-binding proteins of 120-140 kDa but show additional bands at 60-70 kDa; the relationship of the smaller proteins to the larger ones is unclear. The nucleotide sequence indicates that the full-length cDNA encodes 810 amino acids including the signal sequence. While no consensus sequence for protein kinases is present in the cytoplasmic domain, a sequence comparison with the erythropoietin receptor, the IL-6 receptor, and the beta chain of the IL-2 receptor reveals a significant homology in the extracellular domain, indicating that the IL-4 receptor is a member of a cytokine receptor family.
Department of Immunology, DNAX Research Institute of Molecular and Cellular Biology, Palo Alto, CA 94304.
N
N
Harada
B E
BE
Castle
D M
DM
Gorman
N
N
Itoh
J
J
Schreurs
R L
RL
Barrett
M
M
Howard
A
A
Miyajima
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics* / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D015723:Gene Library; D005796:Genes; D006801:Humans; D015847:Interleukin-4 / Q000378:metabolism; D008024:Ligands; D051379:Mice; D008969:Molecular Sequence Data; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen / Q000235:genetics* / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D014162:Transfection
D008024:Ligands; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen; D015847:Interleukin-4; D004247:DNA