6GRS

Paired immunoglobulin-like receptor B (PirB) or Leukocyte immunoglobulin-like receptor subfamily B member 3 (LILRB3) full extracellular domain

Summary for 6GRS

• Entry DOI: 10.2210/pdb6grs/pdb
• Descriptor: Paired immunoglobulin-like receptor B, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, 2-acetamido-2-deoxy-beta-D-glucopyranose (3 entities in total)
• Functional Keywords: neuronal growth inhibition, b cell down regulation, immune system
• Biological source: Mus musculus (House Mouse)
• Total number of polymer chains: 2
• Total formula weight: 135558.34

Authors

Vlieg, H.C.,Huizinga, E.G.,Janssen, B.J.C. (deposition date: 2018-06-12, release date: 2019-02-06, Last modification date: 2024-01-17)

Primary citation

Vlieg, H.C.,Huizinga, E.G.,Janssen, B.J.C.
Structure and flexibility of the extracellular region of the PirB receptor.
J.Biol.Chem., 294:4634-4643, 2019

PubMed Abstract: Murine paired immunoglobulin receptor B (PirB) and its human ortholog leukocyte immunoglobulin-like receptor B2 (LILRB2) are widely expressed inhibitory receptors that interact with a diverse set of extracellular ligands and exert functions ranging from down-regulation of immune responses to inhibition of neuronal growth. However, structural information that could shed light on how PirB interacts with its ligands is lacking. Here, we report crystal structures of the PirB ectodomain; the first full ectodomain structure for a LILR family member, at 3.3-4.5 Å resolution. The structures reveal that PirB's six Ig-like domains are arranged at acute angles, similar to the structures of leukocyte immunoglobulin-like receptor (LILR) and killer-cell immunoglobulin-like receptor (KIR). We observe that this regular arrangement is followed throughout the ectodomain, resulting in an extended zigzag conformation. In two out of the five structures reported here, the repeating zigzag is broken by the first domain that can adopt two alternative orientations. Quantitative binding experiments revealed a 9 μm dissociation constant for PirB-myelin-associated glycoprotein (MAG) ectodomain interactions. Taken together, these structural findings and the observed PirB-MAG interactions are compatible with a model for intercellular signaling in which the PirB extracellular domains, which point away from the cell surface, enable interaction with ligands in .

PubMed: 30674550
DOI: 10.1074/jbc.RA118.004396

Experimental method

X-RAY DIFFRACTION (3.4 Å)