Expression of the extracellular region of the human interleukin-4 receptor alpha chain and interleukin-13 receptor alpha1 chain by a silkworm-baculovirus system.
The receptor binding to interleukin (IL)-13 is composed of the IL-13 receptor alpha1 chain (IL-13Ralpha1) and the IL-4 receptor alpha chain (IL-4Ralpha). In order to investigate the interaction of IL-13 with IL-13Ralpha1 and IL-4Ralpha, the DNA fragments coding the extracellular regions of human IL-13Ralpha1 and the IL-4Ralpha (containing a cytokine receptor homologous region) were fused with mouse Fc and expressed by a silkworm-baculovirus system. The expressed receptors were successfully purified by affinity chromatography using protein A, and the Fc region was removed by thrombin digestion. After further purification with anion-exchange chromatography, these receptors were used to investigate the ligand-receptor interaction. Size exclusion chromatography and SPR analysis revealed that mixture of IL-13 and IL-13Ralpha1 showed predominant affinity to IL-4Ralpha, although neither detectable affinity of IL-13 nor IL-13Ralpha1 was observed against IL-4Ralpha. Combining these data with the moderate affinity of IL-13 to IL-13Ralpha1, this indicates that IL-13 first binds to IL-13Ralpha1 and recruits consequently to IL-4R.
Honjo
Eijiro
E
Neutron Biology Research Center, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai, Ibaraki 319-1195, Japan.
Shoyama
Yoshinari
Y
Tamada
Taro
T
Shigematsu
Hideki
H
Hatanaka
Takaaki
T
Kanaji
Sachiko
S
Arima
Kazuhiko
K
Ito
Yuji
Y
Izuhara
Kenji
K
Kuroki
Ryota
R
D000818:Animals; D016367:Baculoviridae / Q000235:genetics*; D012831:Bombyx / Q000235:genetics*; D003001:Cloning, Molecular; D006801:Humans; D053661:Interleukin-13 Receptor alpha1 Subunit / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D053662:Interleukin-4 Receptor alpha Subunit / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D017434:Protein Structure, Tertiary
D053661:Interleukin-13 Receptor alpha1 Subunit; D053662:Interleukin-4 Receptor alpha Subunit