Two high-affinity interleukin 1 receptors represent separate gene products

R Chizzonite1, T Truitt, P L Kilian

  • 1Department of Molecular Genetics, Roche Research Center, Hoffmann-La Roche Inc., Nutley, NJ 07110.

Interleukin 1 (IL-1) is a polypeptide hormone that mediates a broad range of biological activities and interacts with surface receptors on numerous cell types. Equilibrium binding studies have identified a class of IL-1 receptors on T cells, fibroblasts, and epithelial cells that have 2- to 5-fold higher affinity than the receptors on bone marrow cells, pre-B cells, and macrophage cell lines. Affinity cross-linking with human 125I-labeled IL-1 alpha (125I-IL-1 alpha) labels an approximately 100-kDa protein on T cells and fibroblasts and an approximately 80-kDa protein on pre-B cells and macrophage cell lines. Monoclonal and polyclonal antibodies specific for the IL-1 receptor on T cells and fibroblasts block human 125I-IL-1 alpha binding to T cells, fibroblasts, and epithelial cells but cannot block IL-1 binding to bone marrow cells, pre-B cells, and macrophages. These antibodies immunoprecipitate the IL-1 receptor-human 125I-IL-1 alpha complex from T cells and fibroblasts but not from pre-B cells and macrophage cell lines. An S1 nuclease protection assay demonstrated that T cells and fibroblasts contain identical IL-1 receptor mRNA but that pre-B cells and macrophages do not contain this receptor mRNA. Taken together, the data demonstrate that mouse T cells, fibroblasts, and epithelial cells express an identical IL-1 receptor, whereas the IL-1 receptor on pre-B cells, macrophages, and bone marrow cells represents a different gene product.

Related Concept Videos

Leaky Scanning02:28

Leaky Scanning

During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA.  Marilyn Kozak discovered that the sequence RCCAUGG (where R stands for...
Exon Recombination02:32

Exon Recombination

The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes. 
Exon shuffling follows “splice frame rules.” Each exon has three reading...
The JAK-STAT Signaling Pathway01:20

The JAK-STAT Signaling Pathway

Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as  SH2...
Immunoglobulin-like Cell Adhesion Molecules01:31

Immunoglobulin-like Cell Adhesion Molecules

Immunoglobulin-like cell adhesion molecules or Ig-CAMs are a versatile group of cell surface glycoproteins belonging to the immunoglobulin protein superfamily. Ig-CAMs possess the characteristic immunoglobulin protein domains and other domains such as the fibronectin type III domain. The Ig domains are glycosylated to varying degrees in different Ig-CAMs.
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
The Two-State Receptor Model01:29

The Two-State Receptor Model

The two-state receptor model explains a drug's interaction with receptors, such as G protein-coupled receptors and ligand-gated ion channels, to induce or inhibit a biological response. When no natural ligands are present, a receptor exists in an equilibrium of inactive (Ri) and active (Ra) conformations. The inactive form does not produce a response, while the active form generates a basal effect known as constitutive activity.
The binding affinity of a drug determines its interaction with one...
T Cell Types and Functions01:24

T Cell Types and Functions

When T cells with CD4 markers are activated, they give rise to two types of effector cells: helper T cells and regulatory T cells. Meanwhile, T cells with CD8 markers differentiate into effector cytotoxic T cells. The differentiation of CD4 T cells into helper T cell subsets, such as Th1, Th2, and Th17 cells, is dependent on the antigen type, antigen-presenting cell, and regulatory cytokines.
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...