June 1, 2010

Making Enough Red Blood Cells

EMBL scientists identify molecules that ensure red blood cell production

Red blood cells, the delivery men that take oxygen to cells all around the body, have short lives. To keep enough of them in circulation, the human body produces around 2 million of these cells every second "“ even more in response to challenges like severe blood loss. In a study published today in the Journal of Experimental Medicine, scientists at the European Molecular Biology Laboratory (EMBL) in Monterotondo, Italy, and EMBL's European Bioinformatics Institute (EMBL-EBI) in Hinxton, UK, have identified two small RNA molecules which ensure that enough red blood cells are produced efficiently, by fine-tuning a number of different genes involved in this process.

"A lot of the effort of blood cell formation, or haematopoiesis, goes into just keeping enough red blood cells in circulation" says D³nal O'Carroll, who led the work at EMBL Monterotondo: "We've identified two molecules that help to do so, and which are essential in challenging situations."



"Under steady-state conditions, mice without MiR144 or MiR451 can just about produce enough red blood cells, but if you challenge them, by chemically inducing anemia, most of them don't survive, because in those conditions you just can't live with inefficient red blood cell formation" O'Carroll explains.

O'Carroll and colleagues teamed up with Anton Enright's group at EMBL-EBI, and used a sophisticated bioinformatics approach to understand how these microRNAs act. They found that of the two, MiR451 probably plays a key role in the process, and that it likely does so not by switching a single gene on or off, but by fine-tuning a multitude of genes involved in red blood cell formation.


Source Article: Rasmussen, K.D., Simmini, S., Abreu-Goodger, C., Bartonicek, N., Di Giacomo, M., Bilbao-Cortes, D., Horos, R., Von Lindern, M., Enright, A.J., & O'Carroll, D. The miR-144/451 locus is required for erythroid homeostasis, Journal of Experimental Medicine, Published online May 31st, 2010.


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