4H11

Interaction partners of PSD-93 studied by X-ray crystallography and fluorescent polarization spectroscopy

Summary for 4H11

• Entry DOI: 10.2210/pdb4h11/pdb
• Descriptor: Disks large homolog 2, SULFATE ION, ACETATE ION, ... (4 entities in total)
• Functional Keywords: all beta pdz, protein interaction, protein binding, neuropeptide
• Biological source: Rattus norvegicus (rat)
• Cellular location: Cell membrane ; Lipid-anchor : Q63622
• Total number of polymer chains: 2
• Total formula weight: 22358.11

Authors

Fiorentini, M.,Kastrup, J.S.,Gajhede, M. (deposition date: 2012-09-10, release date: 2013-04-03, Last modification date: 2024-02-28)

Primary citation

Fiorentini, M.,Bach, A.,Stromgaard, K.,Kastrup, J.S.,Gajhede, M.
Interaction partners of PSD-93 studied by X-ray crystallography and fluorescence polarization spectroscopy.
Acta Crystallogr.,Sect.D, 69:587-594, 2013

PubMed Abstract: PSD-93 (chapsyn-110, DLG2) is a member of the family of membrane-associated guanylate kinase (MAGUK) proteins. The MAGUK proteins are involved in receptor localization and signalling pathways. The best characterized MAGUK protein, PSD-95, is known to be involved in NMDA receptor signalling via its PDZ domains. The PDZ domains of PSD-95 and PSD-93 are structurally very similar, but relatively little is known about the function of PSD-93. PSD-93 has been suggested to interact with GluD2 from the family of ionotropic glutamate receptors. Here, the interactions of four residues (GTSI) representing the extreme C-terminus of GluD2 with PSD-93 PDZ1 have been investigated in the crystalline phase. Two different binding modes of these residues were observed, suggesting that the peptide is not tightly bound to PSD-93 PDZ1. In accordance, the two N-terminal PSD-93 PDZ domains show no appreciable binding affinity for a GluD2-derived C-terminal octapeptide, whereas micromolar affinity was observed for a GluN2B-derived C-terminal octapeptide. This indicates that if present, the interactions between GluD2 and PSD-93 involve more than the extreme terminus of the receptor. In contrast, the tumour-suppressor protein SCRIB PDZ3 shows low micromolar affinity towards the GluD2-derived octapeptide, which is in agreement with previous findings using high-throughput assays.

PubMed: 23519667
DOI: 10.1107/S0907444912051839

Experimental method

X-RAY DIFFRACTION (1.67 Å)