PDBsum entry 4kfw

Signaling protein

PDB id: 4kfw

Contents

Protein chains

210 a.a.

Waters ×91

PDB id:

4kfw

Name:

Signaling protein

Title:

Structural insight into golgi membrane stacking by grasp65 and grasp55

Structure:

Golgi reassembly stacking protein 2. Chain: a, b. Engineered: yes

Source:

Rattus norvegicus. Brown rat,rat,rats. Organism_taxid: 10116. Gene: gorasp2, rcg_26651. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

2.70Å R-factor: 0.207 R-free: 0.290

Authors:

X.Liu,J.Hu

Key ref:

Y.Feng et al. (2013). Structural insight into Golgi membrane stacking by GRASP65 and GRASP55 proteins. J Biol Chem, 288, 28418-28427. PubMed id: 23940043 DOI: 10.1074/jbc.M113.478024

Date:

28-Apr-13 Release date: 21-Aug-13

Protein chains

Q9R064  (GORS2_RAT) -  Golgi reassembly-stacking protein 2 from Rattus norvegicus

Seq: 454 a.a.

Struc: 210 a.a.*

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

DOI no: 10.1074/jbc.M113.478024

J Biol Chem 288:28418-28427 (2013)

PubMed id: 23940043

Structural insight into Golgi membrane stacking by GRASP65 and GRASP55 proteins.

Y.Feng, W.Yu, X.Li, S.Lin, Y.Zhou, J.Hu, X.Liu.

ABSTRACT

The stacking of Golgi cisternae involves GRASP65 and GRASP55. The oligomerization of the N-terminal GRASP domain of these proteins, which consists of two tandem PDZ domains, is required to tether the Golgi membranes. However, the molecular basis for GRASP assembly is unclear. Here, we determined the crystal structures of the GRASP domain of GRASP65 and GRASP55. The structures reveal similar homotypic interactions: the GRASP domain forms a dimer in which the peptide-binding pockets of the two neighboring PDZ2 domains face each other, and the dimers are further connected by the C-terminal tail of one GRASP domain inserting into the binding pocket of the PDZ1 domain in another dimer. Biochemical analysis suggests that both types of contacts are relatively weak but are needed in combination for GRASP-mediated Golgi stacking. Our results unveil a novel mode of membrane tethering by GRASP proteins and provide insight into the mechanism of Golgi stacking.