4CN0

An intertwined homodimer of the PDZ homology domain of AHNAK2

Summary for 4CN0

• Entry DOI: 10.2210/pdb4cn0/pdb
• Related: 4CMZ
• Descriptor: PROTEIN AHNAK2, TETRAETHYLENE GLYCOL, POTASSIUM ION, ... (4 entities in total)
• Functional Keywords: cell cycle, domain swapping, intertwining, pdz domain
• Biological source: Homo sapiens (HUMAN)
• Cellular location: Nucleus : Q8IVF2
• Total number of polymer chains: 2
• Total formula weight: 22277.89

Authors

Han, H.,Kursula, P. (deposition date: 2014-01-20, release date: 2014-04-02, Last modification date: 2023-12-20)

Primary citation

Han, H.,Kursula, P.
Periaxin and Ahnak Nucleoprotein 2 Form Intertwined Homodimers Through Domain Swapping
J.Biol.Chem., 289:14121-, 2014

PubMed Abstract: Periaxin (PRX) is an abundant protein in the peripheral nervous system, with an important role in myelination. PRX participates in large molecular complexes, most likely through the interactions of its N-terminal PSD-95/Discs-large/ZO-1 (PDZ)-like domain. We present the crystal structures of the PDZ-like domains from PRX and its homologue AHNAK nucleoprotein 2 (AHNAK2). The unique intertwined, domain-swapped dimers provide a structural basis for the homodimerization of both proteins. The core of the homodimer is formed by a 6-stranded antiparallel β sheet, with every other strand from a different chain. The AHNAK2 PDZ domain structure contains a bound class III ligand peptide. The binding pocket is preformed, and the peptide-PDZ interactions have unique aspects, including two salt bridges and weak recognition of the peptide C terminus. Tight homodimerization may be central to the scaffolding functions of PRX and AHNAK2 in molecular complexes linking the extracellular matrix to the cytoskeletal network.

PubMed: 24675079
DOI: 10.1074/JBC.M114.554816

Experimental method

X-RAY DIFFRACTION (1.75 Å)