Researchers at Brigham and Women's Hospital (BWH) have discovered a new gene that regulates hemoglobin synthesis during red blood cell formation. The findings advance the biomedical community's understanding and treatment of human anemias and mitochondrial disorders.
The study will be published online on November 7, 2012 in Nature.
The researchers used an unbiased zebrafish genetic screen to clone mitochondrial ATPase inhibitory factor-1 gene, or Atpif1. The gene allows animals-zebrafish, mice and humans for instance-to efficiently make hemoglobin. Hemoglobin is the protein in red blood cells responsible for transporting oxygen in the blood.
The researchers found that loss of Atpif1 causes severe anemia. Moreover, the researchers uncovered a broader mechanistic role for Atpif1-regulating the enzymatic activity of ferrochelatase, or Fech. Fech is the terminal enzyme in heme (a component of hemoglobin) synthesis.
"Our study has established a unique functional link between Atpif1-regulated mitochondrial pH, redox potential, and [2Fe-2S] cluster binding to Fech in modulating its heme synthesis," said Dhvanit Shah, PhD, BWH Division of Hematology, Department of Medicine, first study author.
The researchers were also able to produce data on the human version of Atpif1, noting its functional importance for normal red blood cell differentiation, and noting that a deficiency may contribute to human diseases, such as congenital sideroblastic anemias and other diseases related to dysfunctional mitochondria (the energy powerhouses of cells).