Structure and mechanism of blood-brain-barrier lipid transporter MFSD2A.
Wood, C.A.P., Zhang, J., Aydin, D., Xu, Y., Andreone, B.J., Langen, U.H., Dror, R.O., Gu, C., Feng, L.(2021) Nature 596: 444-448
- PubMed: 34349262 
- DOI: https://doi.org/10.1038/s41586-021-03782-y
- Primary Citation of Related Structures:  
7N98 - PubMed Abstract: 
MFSD2A is a sodium-dependent lysophosphatidylcholine symporter that is responsible for the uptake of docosahexaenoic acid into the brain 1,2 , which is crucial for the development and performance of the brain 3 . Mutations that affect MFSD2A cause microcephaly syndromes 4,5 . The ability of MFSD2A to transport lipid is also a key mechanism that underlies its function as an inhibitor of transcytosis to regulate the blood-brain barrier 6,7 . Thus, MFSD2A represents an attractive target for modulating the permeability of the blood-brain barrier for drug delivery. Here we report the cryo-electron microscopy structure of mouse MFSD2A. Our structure defines the architecture of this important transporter, reveals its unique extracellular domain and uncovers its substrate-binding cavity. The structure-together with our functional studies and molecular dynamics simulations-identifies a conserved sodium-binding site, reveals a potential lipid entry pathway and helps to rationalize MFSD2A mutations that underlie microcephaly syndromes. These results shed light on the critical lipid transport function of MFSD2A and provide a framework to aid in the design of specific modulators for therapeutic purposes.
Organizational Affiliation: 
Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA.