• Keine Ergebnisse gefunden

The crystal structure of gephyrin G and E domain reveal a trimeric and dimeric composition.

N/A
N/A
Info
Herunterladen
Protected

Academic year: 2021

Aktie "The crystal structure of gephyrin G and E domain reveal a trimeric and dimeric composition. "

Copied!
1
0
0

Wird geladen.... (Jetzt Volltext ansehen)

Jetzt herunterladen ( 1 Seite )

Volltext

(1)

Abstract

Gephyrin is the major scaffolding protein which develops a lattice underneath the postsynaptic membrane of inhibitory synapses. It clusters and immobilizes Glycine receptors (GlyRs) and γ-aminobutyric acid receptors (GABA

A

Rs) in the postsynaptic membrane by interaction with the cytoskeleton. At the same time gephyrin also interacts with certain other proteins which play a regulatory role in synaptic clustering. Amongst others gephyrin binds to the dynein light chain 1 and 2 (DLC1 and 2) of the LC8 family which are components of the cytoplasmic dynein motor complex and the myosin V motor.

The crystal structure of gephyrin G and E domain reveal a trimeric and dimeric composition.

The structure of the central C domain remains unknown. For a better understanding how the molecular scaffold of gephyrin is established at the postsynaptic membrane the knowledge of the structural formation of the C domain is necessary. DLC1 and 2 bind gephyrin in the N-terminal region of the C domain. After expression and purification of the proteins the stability of gepyhrin was analyzed in the absence and presence of DLC 1 and 2 by partial proteolysis and differential scanning calorimetry (DSC). The results showed that the C domain is rapidly degraded that might result from a surface exposed location in the overall structure and an unstructured formation. Binding of DLC1 and 2 lead to an increased stability. Based on these results truncated gephyrin variants were cloned and expressed which were used for crystallization but unfortunately no crystals were obtained. Detailed binding parameters from isothermal titration calorimetry and analytical gelfiltration showed a 3 : 2 stoichiometry of the gephyrin / DLC1 complex. This ratio shifted to 3 : 1 in the complex of the truncated gephyrin variants and DLC1 as well as for the isolated C domain with DLC1.

The DLC mediated transport is based on a simultaneous binding of DLC1 to cargo molecules and the dynein motor complex. Cosedimentation experiments, analytical gelfiltration and colocalization in non neuronal cells disprove the formation of a ternary complex established by gephyrin, DLC1 and dynein intermediate chain 1 and 2 (DIC1 and 2) which makes a DLC mediated transport of gephyrin unlikely.

To investigate the function of gephyrin and DLC1 in more detail variants of both proteins

were established which are not able to bind each other. Colocalization in Cos-7 cells showed

a reduced binding of gephyrin and DLC1. The analysis of these variants in hippocampal

neurons showed a reduced localization of gephyrin cluster at the synapse which might

indicate a regulatory function of the interaction of gephyrin and DLC.

Referenzen

Jetzt herunterladen ( PDF - 1 Seite - 17.73 KB )

ÄHNLICHE DOKUMENTE

Synthesis, Crystal Structure and Magnetic Properties of a Mn(II) Fluorenedicarboxylate Complex

The Mn(II) ion is coordinated by four oxygen atoms from four different H 2 DFDC ligands and two nitrogen atoms from one phen ligand in an octahedral coordination geometry.. The

Synthesis and Structure of the Ternary Vanadate NaMn

a Institut f¨ur Anorganische und Analytische Chemie, Universit¨at M¨unster, Corrensstraße 30, 48149 M¨unster, Germany. b ICMCB, CNRS, Universit´e

Synthesis and Structure of the Ternary Vanadate NaMn

Mn2O 6 octahedra in successive ribbons along a or b are connected with each other by sharing edges with the Mn1O 6 octahe- dra and corners with the V2O 4 tetrahedra (Fig.

Synthesis and Crystal Structure of the Triple-decker Complex [(η5-C5

c Organisch-Chemisches Institut der Universit¨at Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany Reprint requests to Prof. Scherer on the occasion of his 75

Synthesis and Crystal Structure of the Triple-decker Complex [(η

The reaction of 2 with dppe in CH 2 Cl 2 afforded, after column chromatography of the reaction mix- ture, the neutral complex 3 rather than the cationic complex 4 (Scheme 1)..

Synthesis, Crystal Structure and Antitumor Study of a Cobalt(II) Complex of the 2-Acetylpyrazine Thiosemicarbazone

The complex consists of discrete monomeric molecules with octahedrally hexa- coordinate cobalt(II) ions, where two acetylpyrazine thiosemicarbazones act as NNS tridentate lig-

Synthesis, Crystal Structure and Antitumor Study of a Cobalt(II) Complex of the 2-Acetylpyrazine Thiosemicarbazone

In our earlier studies, it also was found that the cobalt complex of another thiosemicarbazone ligand exhibited poorer antitumor activity compared to the free ligand against the

Synthesis, Crystal Structure and Antitumor Study of a Zinc Complex of the 2-Benzoylpyridine Thiosemicarbazone Ligand

A zinc complex of the 2-benzoylpyridine thiosemicarbazone (Hbpt) ligand, Zn(bpt) 2 · DMF, has been synthesized and characterized by elemental analysis, IR spectra and single