PDBsum entry 5e6s

Cell adhesion

PDB id: 5e6s

Contents

Protein chains

579 a.a.

455 a.a.

Ligands

NAG ×9

Metals

_MG ×3

_CA ×15

Waters ×2052

PDB id:

5e6s

Name:

Cell adhesion

Title:

Structures of leukocyte integrin alb2: the ai domain, the headpiece, and the pocket for the internal ligand

Structure:

Integrin alpha-l. Chain: a, c, e. Fragment: unp residues 26-770. Synonym: cd11 antigen-like family member a,leukocyte adhesion glycoprotein lfa-1 alpha chain,lfa-1a,leukocyte function-associated molecule 1 alpha chain. Engineered: yes. Integrin beta-2. Chain: b, d, f.

Source:

Homo sapiens. Human. Organism_taxid: 9606. Gene: itgal, cd11a. Expressed in: homo sapiens. Expression_system_taxid: 9606. Gene: itgb2, cd18, mfi7. Expression_system_taxid: 9606

Resolution:

2.15Å R-factor: 0.196 R-free: 0.234

Authors:

T.A.Springer,M.Sen

Key ref:

M.Sen and T.A.Springer (2016). Leukocyte integrin αLβ2 headpiece structures: The αI domain, the pocket for the internal ligand, and concerted movements of its loops. Proc Natl Acad Sci U S A, 113, 2940-2945. PubMed id: 26936951 DOI: 10.1073/pnas.1601379113

Date:

10-Oct-15 Release date: 02-Mar-16

Protein chains

P20701  (ITAL_HUMAN) -  Integrin alpha-L from Homo sapiens

Seq: 1170 a.a.

Struc: 579 a.a.*

Protein chains

P05107  (ITB2_HUMAN) -  Integrin beta-2 from Homo sapiens

Seq: 769 a.a.

Struc: 455 a.a.*

* PDB and UniProt seqs differ at 3 residue positions (black crosses)

DOI no: 10.1073/pnas.1601379113

Proc Natl Acad Sci U S A 113:2940-2945 (2016)

PubMed id: 26936951

Leukocyte integrin αLβ2 headpiece structures: The αI domain, the pocket for the internal ligand, and concerted movements of its loops.

M.Sen, T.A.Springer.

ABSTRACT

High-resolution crystal structures of the headpiece of lymphocyte function-associated antigen-1 (integrin αLβ2) reveal how the αI domain interacts with its platform formed by the α-subunit β-propeller and β-subunit βI domains. The αLβ2 structures compared with αXβ2 structures show that the αI domain, tethered through its N-linker and a disulfide to a stable β-ribbon pillar near the center of the platform, can undergo remarkable pivoting and tilting motions that appear buffered by N-glycan decorations that differ between αL and αX subunits. Rerefined β2 integrin structures reveal details including pyroglutamic acid at the β2 N terminus and bending within the EGF1 domain. Allostery is relayed to the αI domain by an internal ligand that binds to a pocket at the interface between the β-propeller and βI domains. Marked differences between the αL and αX subunit β-propeller domains concentrate near the binding pocket and αI domain interfaces. Remarkably, movement in allostery in the βI domain of specificity determining loop 1 (SDL1) causes concerted movement of SDL2 and thereby tightens the binding pocket for the internal ligand.