Researchers at the Gladstone Institute of Cardiovascular Disease (GICD) and the University of California, San Francisco have identified for the first time how tiny genetic factors called microRNAs may influence the differentiation of pluripotent embryonic stem (ES) cells into cardiac muscle. As reported in the journal Cell Stem Cell, scientists in the lab of GICD Director, Deepak Srivastava, MD, demonstrated that two microRNAs, miR-1 and miR-133, which have been associated with muscle development, not only encourage heart muscle formation, but also actively suppress genes that could turn the ES cells into undesired cells like neurons or bone.
“Understanding how pluripotent stem cells can be used in therapy requires that we understand the myriad processes and factors that influence cell fate,” said Dr. Srivastava. “This work shows that microRNAs can function both in directing how ES cells change into specific cells—as well as preventing these cells from developing into unwanted cell types. ”
The differentiation of ES cells into heart cells or any other type of adult cell is a very complicated process involving many factors. MicroRNAS, or miRNAs, seem to act as rheostats or “dimmer switches” to fine-tune levels of important proteins in cells. More than 450 human miRNAs have been described and each is predicted to regulate tens if not hundreds of proteins that may determine cellular differentiation.
While many ES cell-specific miRNAs have been identified, the role of individual miRNAs in ES cell differentiation had not previously been determined. The Gladstone team showed that miRNAs can control how pluripotent stem cells determine their fate, or “cell lineage” – in this case as cardiac muscle cells.
Specifically, they found that miR-1 and miR-133 are active at the early stages of heart cell formation, when an ES cell is first “deciding” to become mesoderm, one of the three basic tissue layers in mammals and other organisms. Activity of either miR-1 or miR-133 in ES cells caused genes that encourage mesoderm formation to be turned on. Equally important, they caused other genes that would have told the cell to become ectoderm or endoderm to turn off. For example, expression of a specific factor called Delta-like 1 was repressed by miR-1. Removal of this factor from cells by other methods also caused the cells to begin transforming into heart cells.
“Our findings provide insight into the fine regulation of cells and genes that is needed for a heart to form,” said Kathy Ivey, PhD, a California Institute of Regenerative Medicine (CIRM) postdoctoral fellow and lead author on the study. “By better understanding this complicated system, in the future, we may be able to identify ways to treat or prevent childhood and adult diseases that affect the heart.”
Valerie Tucker | EurekAlert!
Turning carbon dioxide into liquid fuel
06.08.2020 | DOE/Argonne National Laboratory
Tellurium makes the difference
06.08.2020 | Friedrich-Schiller-Universität Jena
Scientists at the Fraunhofer Institute for Laser Technology ILT have come up with a striking new addition to contact stamping technologies in the ERDF research project ScanCut. In collaboration with industry partners from North Rhine-Westphalia, the Aachen-based team of researchers developed a hybrid manufacturing process for the laser cutting of thin-walled metal strips. This new process makes it possible to fabricate even the tiniest details of contact parts in an eco-friendly, high-precision and efficient manner.
Plug connectors are tiny and, at first glance, unremarkable – yet modern vehicles would be unable to function without them. Several thousand plug connectors...
An international research team has found a new approach that may be able to reduce bone loss in osteoporosis and maintain bone health.
Osteoporosis is the most common age-related bone disease which affects hundreds of millions of individuals worldwide. It is estimated that one in three women...
Traditional single-cell sequencing methods help to reveal insights about cellular differences and functions - but they do this with static snapshots only...
“Core-shell” clusters pave the way for new efficient nanomaterials that make catalysts, magnetic and laser sensors or measuring devices for detecting electromagnetic radiation more efficient.
Whether in innovative high-tech materials, more powerful computer chips, pharmaceuticals or in the field of renewable energies, nanoparticles – smallest...
An international research team with Prof. Cornelia Denz from the Institute of Applied Physics at the University of Münster develop for the first time light fields using caustics that do not change during propagation. With the new method, the physicists cleverly exploit light structures that can be seen in rainbows or when light is transmitted through drinking glasses.
Modern applications as high resolution microsopy or micro- or nanoscale material processing require customized laser beams that do not change during...
23.07.2020 | Event News
21.07.2020 | Event News
07.07.2020 | Event News
06.08.2020 | Earth Sciences
06.08.2020 | Power and Electrical Engineering
06.08.2020 | Life Sciences