5I2Q

Structure of EF-hand containing protein

Summary for 5I2Q

• Entry DOI: 10.2210/pdb5i2q/pdb
• Related: 5I2L 5I2O
• Descriptor: EF-hand domain-containing protein D2, CALCIUM ION (3 entities in total)
• Functional Keywords: calcium binding protein, metal binding protein
• Biological source: Homo sapiens (Human)
• Cellular location: Membrane raft : Q96C19
• Total number of polymer chains: 1
• Total formula weight: 13691.78

Authors

Park, K.R.,Kwon, M.S.,An, J.Y.,Lee, J.G.,Youn, H.S.,Lee, Y.,Kang, J.Y.,Kim, T.G.,Lim, J.J.,Park, J.S.,Lee, S.H.,Song, W.K.,Cheong, H.,Jun, C.,Eom, S.H. (deposition date: 2016-02-09, release date: 2016-12-28, Last modification date: 2023-11-08)

Primary citation

Park, K.R.,Kwon, M.S.,An, J.Y.,Lee, J.G.,Youn, H.S.,Lee, Y.,Kang, J.Y.,Kim, T.G.,Lim, J.J.,Park, J.S.,Lee, S.H.,Song, W.K.,Cheong, H.K.,Jun, C.D.,Eom, S.H.
Structural implications of Ca(2+)-dependent actin-bundling function of human EFhd2/Swiprosin-1.
Sci Rep, 6:39095-39095, 2016

PubMed Abstract: EFhd2/Swiprosin-1 is a cytoskeletal Ca-binding protein implicated in Ca-dependent cell spreading and migration in epithelial cells. EFhd2 domain architecture includes an N-terminal disordered region, a PxxP motif, two EF-hands, a ligand mimic helix and a C-terminal coiled-coil domain. We reported previously that EFhd2 displays F-actin bundling activity in the presence of Ca and this activity depends on the coiled-coil domain and direct interaction of the EFhd2 core region. However, the molecular mechanism for the regulation of F-actin binding and bundling by EFhd2 is unknown. Here, the Ca-bound crystal structure of the EFhd2 core region is presented and structures of mutants defective for Ca-binding are also described. These structures and biochemical analyses reveal that the F-actin bundling activity of EFhd2 depends on the structural rigidity of F-actin binding sites conferred by binding of the EF-hands to Ca. In the absence of Ca, the EFhd2 core region exhibits local conformational flexibility around the EF-hand domain and C-terminal linker, which retains F-actin binding activity but loses the ability to bundle F-actin. In addition, we establish that dimerisation of EFhd2 via the C-terminal coiled-coil domain, which is necessary for F-actin bundling, occurs through the parallel coiled-coil interaction.

PubMed: 27974828
DOI: 10.1038/srep39095

Experimental method

X-RAY DIFFRACTION (1.935 Å)