First immunoglobulin (Ig)-like domain of X-linked interleukin-1 receptor accessory protein-like 1 (IL1RAPL-1)
Ig1_ IL1RAPL-1_like: domain similar to the first immunoglobulin (Ig)-like domain of X-linked interleukin-1 receptor accessory protein-like 1 (IL1RAPL-1). IL-1 alpha and IL-1 beta are cytokines which participates in the regulation of inflammation, immune responses, and hematopoiesis. These cytokines bind to the IL-1 receptor type 1 (IL1R1), which is activated on additional association with an accessory protein, IL1RAP. IL-1 also binds a second receptor designated type II (IL1R2). Mature IL1R1 consists of three Ig-like domains, a transmembrane domain, and a large cytoplasmic domain. Mature IL1R2 is organized similarly except that it has a short cytoplasmic domain. The latter does not initiate signal transduction. A naturally occurring cytokine IL-1RA (IL-1 receptor antagonist) is widely expressed and binds to IL-1 receptors, inhibiting the binding of IL-1 alpha and IL-1 beta. IL1RAPL is encoded by a gene on the X-chromosome, this gene is wholly or partially deleted in multiple cases of non-syndromic mental retardation. This group also contains IL1RAPL-2, which is also encoded by a gene on the X-chromosome and is a candidate for another non-syndromic mental retardation loci.