The data may help stem cell researchers understand the mechanisms that determine whether stem cells divide or differentiate, what types of cells they become and how to control those complex mechanisms to facilitate development of new therapies. The study was published in the August 6 issue of the journal Cell Stem Cell.
Protein phosphorylation, the biochemical process that modifies protein activities by adding a phosphate molecule, is central to cell signaling. Using sophisticated phosphoproteomic analyses, the team of Sheng Ding, Ph.D., associate professor at TSRI, Evan Y. Snyder, M.D., Ph.D., professor and director of Burnham’s Stem Cell and Regenerative Biology program, and Laurence M. Brill, Ph.D., senior scientist at Burnham’s Proteomics Facility, catalogued 2,546 phosphorylation sites on 1,602 phosphoproteins. Prior to this research, protein phosphorylation in hESCs was poorly understood. Identification of these phosphorylation sites provides insights into known and novel hESC signaling pathways and highlights signaling mechanisms that influence self-renewal and differentiation.
“This research will be a big boost for stem cell scientists,” said Dr. Brill. “The protein phosphorylation sites identified in this study are freely available to the broader research community, and researchers can use these data to study the cells in greater depth and determine how phosphorylation events determine a cell’s fate.”
The team performed large-scale, phosphoproteomic analyses of hESCs and their differentiated derivatives using multi-dimensional liquid chromatography and tandem mass spectrometry. The researchers then used the phosphoproteomic data as a predictive tool to target a sample of the signaling pathways that were revealed by the phosphorylated proteins in hESCs, with follow-up experiments to confirm the relevance of these phosphoproteins and pathways to the cells. The study showed that many transcription regulators such as epigenetic and transcription factors, as well as a large number of kinases are phosphorylated in hESCs, suggesting that these proteins may play a key role in determining stem cell fate. Proteins in the JNK signaling pathway were also found to be phosphorylated in undifferentiated hESCs, which suggested that inhibition of JNK signaling may lead to differentiation, a result that was confirmed in hESC cultures.
These methods were extremely useful to discover novel proteins relevant to the human embryonic stem cells. For example, the team found that phosphoproteins in receptor tyrosine kinase (RTK) signaling pathways were numerous in undifferentiated hESCs. Follow-up studies used this unexpected finding to show that multiple RTKs can support hESCs in their undifferentiated state.
This research shows that phosphoproteomic data can be a powerful tool to broaden understanding of hESCs and how their ultimate fate is determined. With this knowledge, stem cell researchers may be able to develop more focused methods to control hESC differentiation and move closer to clinical therapies.
The protein phosphorylation data is available on the Cell Stem Cell website, as well as on the PRIDE website, www.ebi.ac.uk/pride.About Burnham Institute for Medical Research
Josh Baxt | Newswise Science News
Further reports about: > Medical Wellness > RTK > Stem cell innovation > TSRI > Tick Size > cell death > drug discovery > embryonic stem cell > medical research > methanol fuel cells > phosphoproteomic data > signaling pathway > stem cell research > stem cells > transcription factor > transcription regulators
When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short
23.03.2017 | Institut für Pflanzenbiochemie
WPI team grows heart tissue on spinach leaves
23.03.2017 | Worcester Polytechnic Institute
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
23.03.2017 | Life Sciences
23.03.2017 | Power and Electrical Engineering
23.03.2017 | Earth Sciences