PROSITE documentation PDOC00226 [for PROSITE entry PS00253]

Interleukin-1 signature


Interleukin-1 (IL-1) [1,2,3] is a member of a family of cellular mediators known as cytokines. IL-1 has many biological activities. Among other functions, it is a fever-producing factor (pyrogen), induces prostaglandin synthesis, is involved in T-lymphocyte activation and proliferation as well as in B-lymphocyte activation and proliferation via interleukin-2.

There are two different forms of IL-1: IL-1 α and IL-1 β, whose sequence are about 25% identical. IL-1 α and β bind to the same receptor. Both forms of IL-1 are synthesized as precursor proteins of about 270 residues which are then post-translationally processed by the cleavage of a N-terminal sequence of approximately 115 residues.

The interleukin-1 receptor antagonist (IL-1ra) is a protein structurally related to IL-1's but whose biological function is not yet known.

As a signature pattern for these cytokines, we selected a conserved region in the C-terminal section.

Last update:

November 1997 / Text revised.

Technical section

PROSITE method (with tools and information) covered by this documentation:

INTERLEUKIN_1, PS00253; Interleukin-1 signature  (PATTERN)


1AuthorsDinarello C.A.
TitleBiology of interleukin 1.
SourceFASEB J. 2:108-115(1988).
PubMed ID3277884

2AuthorsMizel S.B.
TitleThe interleukins.
SourceFASEB J. 3:2379-2388(1989).
PubMed ID2676681

3AuthorsHughes A.L.
TitleEvolution of the interleukin-1 gene family in mammals.
SourceJ. Mol. Evol. 39:6-12(1994).
PubMed ID8064874

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