Molecular mechanism of choline and ethanolamine transport in humans.

Human feline leukaemia virus subgroup C receptor-related proteins 1 and 2 (FLVCR1 and FLVCR2) are members of the major facilitator superfamily. Their dysfunction is linked to several clinical disorders, including PCARP, HSAN and Fowler syndrome. Earlier studies concluded that FLVCR1 may function as a haem exporter, whereas FLVCR2 was suggested to act as a haem importer, yet conclusive biochemical and detailed molecular evidence remained elusive for the function of both transporters.

Snapshots of ABCG1 and ABCG5/G8: A Sterol's Journey to Cross the Cellular Membranes.

The subfamily-G ATP-binding cassette (ABCG) transporters play important roles in regulating cholesterol homeostasis. Recent progress in the structural data of ABCG1 and ABCG5/G8 disclose putative sterol binding sites that suggest the possible cholesterol translocation pathway. ABCG1 and ABCG5/G8 share high similarity in the overall molecular architecture, and both transporters appear to use several unique structural motifs to facilitate cholesterol transport along this pathway, including the phenylalanine highway and the hydrophobic valve.