Expression and purification of the heme exporter FLVCR1a.

With many crucial roles in enzymatic aerobic metabolism, the concentration of the heme must be tightly regulated. The heme exporter Feline Leukemia Virus sub-group C Receptor 1a (FLVCR1a), an integral membrane protein with twelve transmembrane helices, is a key player in the maintenance of cellular heme homeostasis. It was first identified as the host receptor for the Feline Leukemia Virus sub-group C (FeLV-C), a retrovirus causing hematological abnormalities in cats and other felines. Mutations in the Flvcr1 were later identified in human patients affected by Posterior Column Ataxia and Retinitis Pigmentosa (PCARP) and Hereditary Sensory and Autonomic Neuropathies (HSANs). Despite being an essential component in heme balance, currently there is a lack in the understanding of its function at the molecular level, including the effect of disease-causing mutations on protein function and structure. Therefore, there is a need for protocols to achieve efficient recombinant production yielding milligram amounts of highly pure protein to be used for biochemical and structural studies. Here, we report the first FLVCR1a reliable protocol suitable for both antibody generation and structural characterisation.