The GLRX5 gene contains 2 exons and encodes for a protein that is 13 kDa in size. The protein is highly expressed in erythroid cells.[7]Crystal structure of the GLRX5 protein reveals that the protein likely exists as a tetramer with two Fe-S clusters buried in the interior.[8]
GLRX5 is a mitochondrial protein is conserved evolutionarily and plays a role in the formation of iron-sulfur clusters, which function to maintain iron homeostasis within the mitochondria and in the cell. GLRX5 is required for the steps in haem synthesis that involves mitochondrial enzymes,[9] and is therefore involved in hematopoiesis. GLRX5 activity is required for normal regulation of hemoglobin synthesis by the iron-sulfur protein ACO1. The function of GLRX5 is highly conserved evolutionarily.[10]
Mutations in the GLRX5 gene have been associated with sideroblastic anemia,[11] variant glycine encephalopathy (also known as non-ketotic hyperglycinemia, NKH).[12] as well as pyridoxine-refractory, autosomal recessive anemia (PRARSA).[10] Cells with mutations in GLRX5 activity show deficiency in Fe-S cluster synthesis, which is likely causative of the observed symptoms.[7]