PDBsum entry: 3dgc

Cytokine/signaling protein

PDB id: 3dgc

Contents

Protein chains

141 a.a. *

202 a.a. *

Ligands

NAG-NAG-BMA-MAN-FUC

IUM

ACT ×2

Metals

_U1 ×11

_CL ×3

Waters ×164

* Residue conservation analysis

PDB id:

3dgc

Name:

Cytokine/signaling protein

Title:

Structure of il-22/il-22r1

Structure:

Interleukin-22. Chain: l, m. Fragment: unp residues 39-179. Synonym: il-22, il-10-related t-cell-derived-inducible fact tif. Mutation: yes. Interleukin-22 receptor subunit alpha-1. Chain: r, s. Fragment: unp residues 19-225.

Source:

Homo sapiens. Human. Organism_taxid: 9606. Organism_taxid: 9606

Resolution:

2.50Å R-factor: 0.222 R-free: 0.270

Authors:

B.C.Jones,N.J.Logsdon,M.R.Walter

Key ref:

B.C.Jones et al. (2008). Structure of IL-22 bound to its high-affinity IL-22R1 chain. Structure, 16, 1333-1344. PubMed id: 18599299 DOI: 10.1016/j.str.2008.06.005

Date:

13-Jun-08 Release date: 15-Jul-08

Protein chains

Q9GZX6  (IL22_HUMAN) -  Interleukin-22

Seq: 179 a.a.

Struc: 141 a.a.*

Protein chains

Q8N6P7  (I22R1_HUMAN) -  Interleukin-22 receptor subunit alpha-1

Seq: 574 a.a.

Struc: 202 a.a.*

* PDB and UniProt seqs differ at 5 residue positions (black crosses)

 Gene Ontology (GO) functional annotation 

• Cellular component: extracellular region (2 terms)
• Biological process: cell-cell signaling (3 terms)
• Biochemical function: protein binding (3 terms)

DOI no: 10.1016/j.str.2008.06.005

Structure 16:1333-1344 (2008)

PubMed id: 18599299

Structure of IL-22 bound to its high-affinity IL-22R1 chain.

B.C.Jones, N.J.Logsdon, M.R.Walter.

ABSTRACT

IL-22 is an IL-10 family cytokine that initiates innate immune responses against bacterial pathogens and contributes to immune disease. IL-22 biological activity is initiated by binding to a cell-surface complex composed of IL-22R1 and IL-10R2 receptor chains and further regulated by interactions with a soluble binding protein, IL-22BP, which shares sequence similarity with an extracellular region of IL-22R1 (sIL-22R1). IL-22R1 also pairs with the IL-20R2 chain to induce IL-20 and IL-24 signaling. To define the molecular basis of these diverse interactions, we have determined the structure of the IL-22/sIL-22R1 complex. The structure, combined with homology modeling and surface plasmon resonance studies, defines the molecular basis for the distinct affinities and specificities of IL-22 and IL-10 receptor chains that regulate cellular targeting and signal transduction to elicit effective immune responses.

Selected figure(s)

Figure 1.
Figure 1. Schematic Diagram of Protein Complexes Formed by IL-22 Receptors
Although not shown, IL-10R2 also forms IL-20R1/IL-10R2 and IL-28R1/IL-10R2 cell-surface complexes that activate IL-26, IL-28, and IL-29 signaling.

Figure 2.
Figure 2. Structure of the IL-22/IL-22R1 Complex
(A) Ribbon diagram of the IL-22/IL-22R1 complex. Helix A/AB loop and helix F that form the sIL-22R1 binding site are colored red and blue, respectively. Boxes show the location of (B) and (E), respectively.
(B) IL-22/sIL-22R1 site 1 interface.
(C) Superposition of IL-22/sIL-22R1 and one half of the IL-10/sIL-10R1 dimer structure. IL-22 is colored red, sIL-22R1 is magenta, IL-10 is green, and sIL-10R1 is cyan.
(D) Structural differences, including the role of carbohydrate, between sIL-22R1 and sIL-10R1 D2 domains.
(E) Putative orientation of IL-22/IL-22R1 and IL-10/IL-10R1 cell-surface complexes. The IL-10/IL-10R1 complex is oriented so that the IL-10 dimer twofold axis is perpendicular to the membrane. The helix A/AB loop and helix F residues of IL-10, which form the IL-10R1 binding site, are colored yellow and blue.

The above figures are reprinted from an Open Access publication published by Cell Press: Structure (2008, 16, 1333-1344) copyright 2008.

Figures were selected by the author.