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1alu
From Proteopedia
HUMAN INTERLEUKIN-6
Overview
Interleukin 6 (IL-6) has many biological activities in vivo, and deregulation has been implicated in many disease processes. IL-6, a 185 amino acid polypeptide was refolded, purified and crystallized. The crystals diffracted to beyond 1.9 A and the structure was solved using single isomorphous replacement. The X-ray structure of IL-6 is composed of a four helix bundle linked by loops and an additional mini-helix. 157 out of 185 residues are well defined in the final structure, with 18 N-terminal and 8 A-B loop amino acids displaying no interpretable electron density. The three-dimensional structure has been used to construct a model of IL-6 interacting with the IL-6 receptor (alpha-chain) and gp130 (beta-chain) that gives new insight into the process of molecular recognition and signaling. Based on this model, we predict a fourth binding site on IL-6, a low affinity IL-6-IL-6 interaction, which may be necessary for the sequential assembly of a functional hexameric IL-6 receptor complex.
About this Structure
1ALU is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
1.9 A crystal structure of interleukin 6: implications for a novel mode of receptor dimerization and signaling., Somers W, Stahl M, Seehra JS, EMBO J. 1997 Mar 3;16(5):989-97. PMID:9118960 Page seeded by OCA on Fri May 2 10:25:47 2008
