Structure of the functional interleukin-2 receptor. Evidence for the association of human p55 and murine p75 molecules in a mouse T cell line.
The structural basis of the high affinity interleukin-2 receptor which was previously reconstituted in a cultured murine T cell line, EL4 by expressing either wild-type Tac antigen complementary DNA (cDNA) or a chimeric cDNA was characterized. The chimeric cDNA encodes a membrane portion whose extracellular portion consists of that of Tac antigen whereas transmembrane and cytoplasmic portions consists of those the human insulin beta chain. The Tac antigen/anti-Tac antibody complex was treated by chemical crosslinking reagents, purified by goat anti-mouse immunoglobulin (Ig), and was analysed by SDS-PAGE. We here demonstrated the presence in mouse EL4 transfectants of a novel membrane protein which is closely associated with the products of transfected cDNAs in the absence of interleukin-2. The protein is 75 kDa in size and is detected in cells which express high affinity interleukin-2 receptor but not in cells which only express low affinity interleukin-2 receptor. The transmembrane region and the cytoplasmic region of Tac antigen is not necessary for the formation of the complex consisting of Tac antigen and 75 kDa molecule, indicating that a murine 75 kDa molecule associates with Tac antigen extra-cellularly.
Yamaguchi
A
A
Department of Pathology, Sapporo Medical College, Japan.
Ide
T
T
Hatakeyama
M
M
Doi
T
T
Kono
T
T
Uchiyama
T
T
Kikuchi
K
K
Taniguchi
T
T
Uede
T
T
D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D003432:Cross-Linking Reagents; D004247:DNA / Q000235:genetics; D006801:Humans; D007376:Interleukin-2 / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism; D051379:Mice; D015394:Molecular Structure; D008970:Molecular Weight; D015375:Receptors, Interleukin-2 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D014162:Transfection
D003432:Cross-Linking Reagents; D007376:Interleukin-2; D008565:Membrane Proteins; D015375:Receptors, Interleukin-2; D004247:DNA