Malfunctions of the proteins FLVCR1 and FLVCR2 lead to rare hereditary diseases in humans that cause motor, sensory and neurological disorders. Researchers from Fraunhofer ITMP, Goethe University Frankfurt, and the MPI for Biophysics now deciphered the FLVCR proteins’ 3D structures and their previously unknown cellular function. The interdisciplinary team of researchers has shown that the proteins transport the cellular building blocks choline and ethanolamine. Their findings contribute significantly to understanding the pathogenesis of rare diseases and developing new therapies.