Download MendeleyStructural basis for interorganelle phospholipid transport mediated by VAT-1.
Watanabe, Y., Tamura, Y., Kakuta, C., Watanabe, S., Endo, T.(2020) J Biol Chem 295: 3257-3268
- PubMed: 32005660
- DOI: https://doi.org/10.1074/jbc.RA119.011019
- Primary Citation of Related Structures:
6K9Y - PubMed Abstract:
Eukaryotic cells are compartmentalized to form organelles, whose functions rely on proper phospholipid and protein transport. Here we determined the crystal structure of human VAT-1, a cytosolic soluble protein that was suggested to transfer phosphatidylserine, at 2.2 Å resolution. We found that VAT-1 transferred not only phosphatidylserine but also other acidic phospholipids between membranes in vitro Structure-based mutational analyses showed the presence of a possible lipid-binding cavity at the interface between the two subdomains, and two tyrosine residues in the flexible loops facilitated phospholipid transfer, likely by functioning as a gate to this lipid-binding cavity. We also found that a basic and hydrophobic loop with two tryptophan residues protruded from the molecule and facilitated binding to the acidic-lipid membranes, thereby achieving efficient phospholipid transfer.
Organizational Affiliation:
Department of Bioscience, Graduate School of Agriculture, Ehime University, Matsuyama, Ehime 790-8566, Japan; Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kita-ku, Kyoto 603-8555, Japan.
