The interleukin-1 receptor binds the human interleukin-1 alpha precursor but not the interleukin-1 beta precursor.
Both IL-1 alpha and IL-1 beta are initially translated as approximately Mr 30,000 polypeptides and processed to approximately Mr 17,500 prior to, or during, release from macrophages. The current study utilizes an in vitro transcription-translation system to produce these four forms of IL-1 directly from cloned cDNAs, in order to investigate the relative receptor binding and biological activities of the proteins. The data show that the initial translation product from IL-1 beta mRNA must be processed in order to bind to the IL-1 receptor and hence express biological activity. By contrast, the initial translation product of IL-1 alpha mRNA can bind to the IL-1 receptor without further proteolytic processing. These data suggest that the IL-1 biological activity previously associated with proteins having Mr values in the range 30,000-40,000 is due to IL-1 alpha gene products.
D001667:Binding, Competitive; D002460:Cell Line; D004247:DNA / Q000235:genetics; D004274:DNA, Recombinant; D006801:Humans; D007375:Interleukin-1 / Q000235:genetics / Q000378:metabolism*; D008970:Molecular Weight; D014176:Protein Biosynthesis; D011498:Protein Precursors / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000378:metabolism; D011971:Receptors, Immunologic / Q000378:metabolism*; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins / Q000378:metabolism; D014158:Transcription, Genetic
D004274:DNA, Recombinant; D007375:Interleukin-1; D011498:Protein Precursors; D012333:RNA, Messenger; D011971:Receptors, Immunologic; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins; C043830:interleukin 1 precursor; D004247:DNA