Pathways & interactions
Interleukin-1 receptor type II (IPR004077)
Short name: IL-1_rcpt_II-typ
Overlapping homologous superfamilies
Interleukin-1 alpha and interleukin-1 beta (IL-1 alpha and IL-1 beta) are cytokines that participate in the regulation of immune responses, inflammatory reactions, and hematopoiesis [PMID: 2969618]. Two types of IL-1 receptor, each with three extracellular immunoglobulin (Ig)-like domains, limited sequence similarity (28%) and different pharmacological characteristics have been cloned from mouse and human cell lines: these have been termed type I and type II receptors [PMID: 8702856]. The receptors both exist in transmembrane (TM) and soluble forms: the soluble IL-1 receptor is thought to be post-translationally derived from cleavage of the extracellular portion of the membrane receptors.
Both IL-1 receptors appear to be well conserved in evolution, and map to the same chromosomal location [PMID: 1833184]. The receptors can both bind all three forms of IL-1 (IL-1 alpha, IL-1 beta and IL-1RA).
The crystal structures of IL1A and IL1B [PMID: 2602367] have been solved, showing them to share the same 12-stranded beta-sheet structure as both the heparin binding growth factors and the Kunitz-type soybean trypsin inhibitors [PMID: 1738162]. The beta-sheets are arranged in 3 similar lobes around a central axis, 6 strands forming an anti-parallel beta-barrel. Several regions, especially the loop between strands 4 and 5, have been implicated in receptor binding.
The Vaccinia virus genes B15R and B18R each encode proteins with N-terminal hydrophobic sequences, possible sites for attachment of N-linked carbohydrate and a short C-terminal hydrophobic domain [PMID: 1826022]. These properties are consistent with the mature proteins being either virion, cell surface or secretory glycoproteins. Protein sequence comparisons reveal that the gene products are related to each other (20% identity) and to the Ig superfamily. The highest degree of similarity is to the human and murine interleukin-1 receptors, although both proteins are related to a wide range of Ig superfamily members, including the interleukin-6 receptor. A novel method for virus immune evasion has been proposed in which the product of one or both of these proteins may bind interleukin-1 and/or interleukin-6, preventing these cytokines reaching their natural receptors [PMID: 1826022]. A similar gene product from Cowpox virus (CPV) has also been shown to specifically bind murine IL-1 beta [PMID: 1339315].
This entry represents Interleukin-1 receptor, type II, the mature type II IL-1 receptor consists of (i) a ligand binding portion comprising three Ig-like domains; (ii) a single TM domain; and (iii) a short cytoplasmic domain of 29 amino acids [PMID: 1833184]. This contrasts with the ~215 amino acid cytoplasmic domain of the type I receptor, suggesting that the two IL-1 receptors may interact with different signal transduction pathways. The type II receptor is expressed in a number of different tissues, including both B and T lymphocytes, and can be induced in several cell types by treatment with phorbol ester. Both IL-1 receptors appear to be well conserved in evolution, and map to the same chromosomal location. Like the type I receptor, the human type II IL-1 receptor can bind all three forms of IL-1 (IL-1 alpha, IL-1 beta and IL-1RA) [PMID: 1833184].
No terms assigned in this category.
GO:0004910 interleukin-1, Type II, blocking receptor activity
No terms assigned in this category.
- PR01539 (INTRLEUKN1R2)