3TOW

Crystal Structure of the MABP Domain of MVB12B of Human ESCRT-I Complex

Summary for 3TOW

• Entry DOI: 10.2210/pdb3tow/pdb
• Descriptor: Multivesicular body subunit 12B (2 entities in total)
• Functional Keywords: beta prism, membrane binding domain, negatively charged membrane, protein transport
• Biological source: Homo sapiens (human)
• Cellular location: Endosome (Probable): Q9H7P6
• Total number of polymer chains: 1
• Total formula weight: 17227.84

Authors

Boura, E.,Hurley, J.H. (deposition date: 2011-09-06, release date: 2012-01-11, Last modification date: 2024-02-28)

Primary citation

Boura, E.,Hurley, J.H.
Structural basis for membrane targeting by the MVB12-associated beta-prism domain of the human ESCRT-I MVB12 subunit.
Proc.Natl.Acad.Sci.USA, 109:1901-1906, 2012

PubMed Abstract: MVB12-associated β-prism (MABP) domains are predicted to occur in a diverse set of membrane-associated bacterial and eukaryotic proteins, but their existence, structure, and biochemical properties have not been characterized experimentally. Here, we find that the MABP domains of the MVB12A and B subunits of ESCRT-I are functional modules that bind in vitro to liposomes containing acidic lipids depending on negative charge density. The MABP domain is capable of autonomously localizing to subcellular puncta and to the plasma membrane. The 1.3-Å atomic resolution crystal structure of the MVB12B MABP domain reveals a β-prism fold, a hydrophobic membrane-anchoring loop, and an electropositive phosphoinositide-binding patch. The basic patch is open, which explains how it senses negative charge density but lacks stereoselectivity. These observations show how ESCRT-I could act as a coincidence detector for acidic phospholipids and protein ligands, enabling it to function both in protein transport at endosomes and in cytokinesis and viral budding at the plasma membrane.

PubMed: 22232651
DOI: 10.1073/pnas.1117597109

Experimental method

X-RAY DIFFRACTION (1.34 Å)