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 Dónal 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.”
To form red blood cells, large, round cells known as precursors have to become small and disc-shaped, like balls of plasticine squeezed between finger and thumb. In the process, they must also produce the large quantities of haemoglobin that will allow them to transport oxygen, and shrink and dispose of their nucleus. The EMBL scientists found that two microRNAs, called MiR144 and MiR451, control the final stages of this process.
O’Carroll and colleagues genetically engineered mice to have no MiR144 or MiR451. They found that such mice had defects in the final stages of red blood cell formation, but produced red blood cell precursors not only in the bone marrow, but also in large quantities in the spleen. By increasing the number of precursors, the mice compensated for the fact that a smaller percentage of those precursors matured into functional red blood cells, and thus were able to survive with only a mild anaemia.
“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 anaemia, 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.
These microRNA molecules have been conserved throughout vertebrate evolution. They are known to also be important for red blood cell formation in fish, and are likely to play a similar role in humans too. Thus, investigating their function further could help to understand how our own red blood cells are formed, and how defects in that process may lead to conditions such as anaemia.Sonia Furtado
Sonia Furtado | EMBL
Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University
How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy