4Z68

Hybrid structural analysis of the Arp2/3 regulator Arpin identifies its acidic tail as a primary binding epitope

Summary for 4Z68

• Entry DOI: 10.2210/pdb4z68/pdb
• Descriptor: Tankyrase-2, GLU-ILE-ARG-GLU-GLN-GLY-ASP-GLY-ALA-GLU-ASP-GLU, SULFATE ION, ... (4 entities in total)
• Functional Keywords: cell migration, arpin, arp 2/3, actin polymerization, protein binding
• Biological source: Homo sapiens (Human); More
• Cellular location: Cytoplasm: Q9H2K2
• Total number of polymer chains: 2
• Total formula weight: 18533.68

Authors

Fetics, S.K.,Campanacci, V.,Dang, I.,Gautreau, A.,Cherfils, J. (deposition date: 2015-04-04, release date: 2015-12-30, Last modification date: 2024-01-10)

Primary citation

Fetics, S.,Thureau, A.,Campanacci, V.,Aumont-Nicaise, M.,Dang, I.,Gautreau, A.,Perez, J.,Cherfils, J.
Hybrid Structural Analysis of the Arp2/3 Regulator Arpin Identifies Its Acidic Tail as a Primary Binding Epitope.
Structure, 24:252-260, 2016

PubMed Abstract: Arpin is a newly discovered regulator of actin polymerization at the cell leading edge, which steers cell migration by exerting a negative control on the Arp2/3 complex. Arpin proteins have an acidic tail homologous to the acidic motif of the VCA domain of nucleation-promoting factors (NPFs). This tail is predicted to compete with the VCA of NPFs for binding to the Arp2/3 complex, thereby mitigating activation and/or tethering of the complex to sites of actin branching. Here, we investigated the structure of full-length Arpin using synchrotron small-angle X-ray scattering, and of its acidic tail in complex with an ankyrin repeats domain using X-ray crystallography. The data were combined in a hybrid model in which the acidic tail extends from the globular core as a linear peptide and forms a primary epitope that is readily accessible in unbound Arpin and suffices to tether Arpin to interacting proteins with high affinity.

PubMed: 26774128
DOI: 10.1016/j.str.2015.12.001

Experimental method

X-RAY DIFFRACTION (1.859 Å)