【Animal Modeling】-Study found a new mechanism of competition among different iron transport pathways in Drosophila melanogaster

  Recently, Xiao Guiran, a professor at the School of Food and Bioengineering at Hefei University of Technology, led a team to discover that Drosophila melanogaster transferrin1 (transferrin1) is involved in iron transport in vivo and competes with ferritin.

  Drosophila melanogaster is an important model organism with a wide range of applications in genetic and developmental biology. They are small in size, have a short life cycle (about 12 days), are highly fertile, and are easy to raise. In addition, Drosophila has 4 pairs of chromosomes containing about 13,600 genes. Existing studies have shown that the genetic information of Drosophila is very conservative. About 39% of human genes have homologues in Drosophila, and more than 70% of human pathogenic genes have homologues in Drosophila. The above advantages make Drosophila melanogaster a popular model organism for studying metal metabolism.

  Xiao Guiran, the first author and corresponding author of the paper, told the "Science China Journal" reporter that this research is based on an in-depth discussion after the analysis of the iron transport pathway of the secretory pathway. Previously, in Drosophila melanogaster, Xiao Guiran identified the ferroportin dZIP13 located on the secretory pathway in Drosophila melanogaster. It is responsible for supplying iron to the secretory pathway, which is then loaded by ferritin and transported to the body for use. What remains to be discussed is the difference and connection between secretory pathway transport and traditional transferrin transport.

  The experimenters used classical genetic methods to knock down the expression of transferrin 1 in different tissues of Drosophila melanogaster, and found that transferrin 1 produced in the fat body (equivalent to mammalian liver) is very important for the growth and development of Drosophila melanogaster. Further research found that transferrin 1 produced by the fat body is secreted into the hemolymph and can be transported to the intestine to play a role, and after the fat body specifically knocked down the expression of transferrin 1, it leads to accumulation in the intestine of Drosophila These data suggest that transferrin 1 produced by the fat body can transport iron between tissues and is responsible for transporting iron from the intestines to the fat body; through genetic interaction analysis, it was found that in the intestine and Knockdown of transferrin 1 expression in the fat body can significantly rescue the growth failure caused by ferritin knockdown or dZIP13 knockdown; further studies have shown that after transferrin 1 knockdown, more iron is transported into the secretory pathway It is loaded by ferritin and then transported to the body for utilization, suggesting that transferrin 1 competes with ferritin for iron in the intestine.

  This study identifies the function of transferrin 1, one of the Drosophila transferrin homologous family, to be responsible for inter-tissue iron transport, capable of transporting iron from the gut to the fat body, and that transferrin 1 and ferritin compete in the gut Iron relationship. This study provides important clues for future studies on the evolution of iron metabolism and refinement of our understanding of iron metabolism in mammals.