PDBsum entry 2pr9

Endocytosis

PDB id: 2pr9

Contents

Protein chain

254 a.a. *

Ligands

ASP-GLU-GLU-TYR-GLY-TYR-GLU-CYS-LEU-ASP

Waters ×59

* Residue conservation analysis

PDB id:

2pr9

Name:

Endocytosis

Title:

Mu2 adaptin subunit (ap50) of ap2 adaptor (second domain), complexed with gabaa receptor-gamma2 subunit-derived internalization peptide deeygyecl

Structure:

Ap-2 complex subunit mu-1. Chain: a. Fragment: second domain (residues 158-435). Engineered: yes. Gaba(a) receptor subunit gamma-2 peptide. Chain: p. Engineered: yes

Source:

Rattus norvegicus. Norway rat. Organism_taxid: 10116. Gene: ap2m1. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008. Synthetic: yes. Other_details: the peptide was chemically synthesized. This sequence occurs naturally in mouse and rat.

Resolution:

2.51Å R-factor: 0.204 R-free: 0.240

Authors:

A.Vahedi-Faridi,V.Haucke,J.T.Kittler,V.Kukhtina,S.J.Moss,W.Saenger, G.-J.Chen,V.Tretter,K.Smith,Z.Yan,K.Mcainsh,L.Arancibia-Carcamo

Key ref:

J.T.Kittler et al. (2008). Regulation of synaptic inhibition by phospho-dependent binding of the AP2 complex to a YECL motif in the GABAA receptor gamma2 subunit. Proc Natl Acad Sci U S A, 105, 3616-3621. PubMed id: 18305175 DOI: 10.1073/pnas.0707920105

Date:

04-May-07 Release date: 18-Mar-08

Protein chain

P84092  (AP2M1_RAT) -  AP-2 complex subunit mu from Rattus norvegicus

Seq: 435 a.a.

Struc: 254 a.a.

DOI no: 10.1073/pnas.0707920105

Proc Natl Acad Sci U S A 105:3616-3621 (2008)

PubMed id: 18305175

Regulation of synaptic inhibition by phospho-dependent binding of the AP2 complex to a YECL motif in the GABAA receptor gamma2 subunit.

J.T.Kittler, G.Chen, V.Kukhtina, A.Vahedi-Faridi, Z.Gu, V.Tretter, K.R.Smith, K.McAinsh, I.L.Arancibia-Carcamo, W.Saenger, V.Haucke, Z.Yan, S.J.Moss.

ABSTRACT

The regulation of the number of gamma2-subunit-containing GABA(A) receptors (GABA(A)Rs) present at synapses is critical for correct synaptic inhibition and animal behavior. This regulation occurs, in part, by the controlled removal of receptors from the membrane in clathrin-coated vesicles, but it remains unclear how clathrin recruitment to surface gamma2-subunit-containing GABA(A)Rs is regulated. Here, we identify a gamma2-subunit-specific Yxxvarphi-type-binding motif for the clathrin adaptor protein, AP2, which is located within a site for gamma2-subunit tyrosine phosphorylation. Blocking GABA(A)R-AP2 interactions via this motif increases synaptic responses within minutes. Crystallographic and biochemical studies reveal that phosphorylation of the Yxxvarphi motif inhibits AP2 binding, leading to increased surface receptor number. In addition, the crystal structure provides an explanation for the high affinity of this motif for AP2 and suggests that gamma2-subunit-containing heteromeric GABA(A)Rs may be internalized as dimers or multimers. These data define a mechanism for tyrosine kinase regulation of GABA(A)R surface levels and synaptic inhibition.

Selected figure(s)

Figure 3.
Crystal structure of the GABA[A]R γ2-subunit YECL-pep complexed with μ2–AP2 (157–435). (A) Ribbon diagram showing the binding site within the signal-binding domain of μ2–AP2 complexed with a peptide corresponding to GABA[A]R γ2-subunit residues 362–371 (gold). (B) Surface representation of the γ2 peptide-binding interface with μ2–AP2, including an overlay with the endocytic motif of EGFR (turquoise) to compare binding of the two motifs.

Figure 4.
Structure of the crystallographic dimer complexed with YECL-pep. (A) Structure of the crystallographic dimer showing the elongated banana-shaped binding pocket of a single YGYECL-pep on the μ2–AP2 dimer surface with the second peptide shown in surface representation. (B) Close-up view to show direct molecular interactions between the γ2-subunit YECL-pep and the other monomer in the crystallographic dimer.

Figures were selected by an automated process.