PDBsum entry 2wjs

Cell adhesion

PDB id: 2wjs

Contents

Protein chain

520 a.a. *

Ligands

NAG ×4

Metals

_CA ×3

Waters ×60

* Residue conservation analysis

PDB id:

2wjs

Name:

Cell adhesion

Title:

Crystal structure of the lg1-3 region of the laminin alpha2 chain

Structure:

Laminin subunit alpha-2. Chain: a. Fragment: lg1-3,residues 2136-2475,2480-2565,2579-2746. Synonym: laminin m chain, merosin heavy chain, laminin alpha2 chain. Engineered: yes. Other_details: protein expressed in presence of kifunensine and digested with endoglycosidase h

Source:

Mus musculus. Mouse. Organism_taxid: 10090. Expressed in: homo sapiens. Expression_system_taxid: 9606. Expression_system_cell_line: 293-ebna.

Resolution:

2.80Å R-factor: 0.212 R-free: 0.266

Authors:

F.Carafoli,N.J.Clout,E.Hohenester

Key ref:

F.Carafoli et al. (2009). Crystal Structure of the LG1-3 Region of the Laminin {alpha}2 Chain. J Biol Chem, 284, 22786-22792. PubMed id: 19553699 DOI: 10.1074/jbc.M109.026658

Date:

28-May-09 Release date: 23-Jun-09

Protein chain

Q60675  (LAMA2_MOUSE) -  Laminin subunit alpha-2 from Mus musculus

Seq: 3118 a.a.

Struc: 520 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

DOI no: 10.1074/jbc.M109.026658

J Biol Chem 284:22786-22792 (2009)

PubMed id: 19553699

Crystal Structure of the LG1-3 Region of the Laminin {alpha}2 Chain.

F.Carafoli, N.J.Clout, E.Hohenester.

ABSTRACT

Laminins are large heterotrimeric glycoproteins with many essential functions in basement membrane assembly and function. Cell adhesion to laminins is mediated by a tandem of five laminin G-like (LG) domains at the C terminus of the alpha chain. Integrin binding requires an intact LG1-3 region, as well as contributions from the coiled coil formed by the alpha, beta, and gamma chains. We have determined the crystal structure at 2.8-A resolution of the LG1-3 region of the laminin alpha2 chain (alpha2LG1-3). The three LG domains adopt typical beta-sandwich folds, with canonical calcium binding sites in LG1 and LG2. LG2 and LG3 interact through a substantial interface, but LG1 is completely dissociated from the LG2-3 pair. We suggest that the missing gamma chain tail may be required to stabilize the interaction between LG1 and LG2-3 in the biologically active conformation. A global analysis of N-linked glycosylation sites shows that the beta-sandwich faces of LG1 are free of carbohydrate modifications in all five laminin alpha chains, suggesting that these surfaces may harbor the integrin binding site. The alpha2LG1-3 structure provides the first atomic view of the integrin binding region of laminins.

Selected figure(s)

Figure 1.
Crystal structure of laminin α2LG1-3.A, schematic representation of the structure. LG1, LG2, and LG3 are in green, blue, and brown, respectively. Disulfide bridges are in yellow, N-linked carbohydrate moieties are in magenta, and calcium ions are shown as sky blue spheres. Disordered regions of the polypeptide chain are indicated by dotted lines. The location of the RRKRR motif in LG3 (see text) is indicated. B, stereoview of a superposition of Cα traces of LG1 (green), LG2 (blue), and LG3 (brown). Disulfide bridges are shown as thick sticks. The 14 canonical β-strands of laminin LG domains (31) have been labeled sequentially, A–N.

Figure 4.
Location of N-linked glycosylation sites in the LG1-3 structure. Shown are two surface representations of the α2LG1-3 structure (LG1, green; LG2, blue; LG3, brown) related by a rotation of 180° about a vertical axis. The LG1-2 linker is shown as a black line. The predicted attachment site in LG1 of the coiled coil region is indicated by a gray arrow. Every N-linked glycosylation site present in one or more of the five mouse or human laminin α chains has been mapped onto the α2LG1-3 structure (see text) and marked by a branched core hexasaccharide (magenta). The left view is similar to the one in Fig. 1A.

The above figures are reprinted from an Open Access publication published by the ASBMB: J Biol Chem (2009, 284, 22786-22792) copyright 2009.

Figures were selected by an automated process.