Red cells need leucine for hemoglobin

Abstract

Physiology Inhibitors of the protein complex mTORC1 are used clinically, but they can cause anemia. Low availability of the amino acid leucine inhibits mTORC1 activity, which suppresses protein synthesis by blocking mRNA translation. The globin proteins in hemoglobin have a particularly high percentage of leucine residues. Chung et al. (see also the Focus by Nathan) found that hemoglobin production by developing red blood cells was decreased by deficiency or inhibition of LAT3, a transporter that enables cells to take up leucine. Specifically, inadequate leucine uptake prevented the translation of globin-encoding transcripts. Sci. Signal. 8 , ra34 and fs9 (2015).