4CKH

Helical reconstruction of ACAP1(BAR-PH domain) decorated membrane tubules by cryo-electron microscopy

Summary for 4CKH

• Entry DOI: 10.2210/pdb4ckh/pdb
• Related: 4CKG
• EMDB information: 2547
• Descriptor: ARF-GAP WITH COILED-COIL, ANK REPEAT AND PH DOMAIN-CONTAINING PROTEIN 1 (1 entity in total)
• Functional Keywords: signaling protein, membrane remodeling
• Biological source: HOMO SAPIENS (HUMAN)
• Cellular location: Recycling endosome membrane ; Peripheral membrane protein ; Cytoplasmic side : Q15027
• Total number of polymer chains: 4
• Total formula weight: 173337.39

Authors

Pang, X.Y.,Fan, J.,Zhang, Y.,Zhang, K.,Gao, B.Q.,Ma, J.,Li, J.,Deng, Y.C.,Zhou, Q.J.,Hsu, V.,Sun, F. (deposition date: 2014-01-06, release date: 2014-10-15, Last modification date: 2024-05-08)

Primary citation

Pang, X.,Fan, J.,Zhang, Y.,Zhang, K.,Gao, B.,Ma, J.,Li, J.,Deng, Y.,Zhou, Q.,Egelman, E.H.,Hsu, V.W.,Sun, F.
A Ph Domain in Acap1 Possesses Key Features of the Bar Domain in Promoting Membrane Curvature.
Dev.Cell, 31:73-, 2014

PubMed Abstract: The BAR (Bin-Amphiphysin-Rvs) domain undergoes dimerization to produce a curved protein structure, which superimposes onto membrane through electrostatic interactions to sense and impart membrane curvature. In some cases, a BAR domain also possesses an amphipathic helix that inserts into the membrane to induce curvature. ACAP1 (Arfgap with Coil coil, Ankyrin repeat, and PH domain protein 1) contains a BAR domain. Here, we show that this BAR domain can neither bind membrane nor impart curvature, but instead requires a neighboring PH (Pleckstrin Homology) domain to achieve these functions. Specific residues within the PH domain are responsible for both membrane binding and curvature generation. The BAR domain adjacent to the PH domain instead interacts with the BAR domains of neighboring ACAP1 proteins to enable clustering at the membrane. Thus, we have uncovered the molecular basis for an unexpected and unconventional collaboration between PH and BAR domains in membrane bending.

PubMed: 25284369
DOI: 10.1016/J.DEVCEL.2014.08.020

Experimental method

ELECTRON MICROSCOPY (17 Å)