A protein that helps maintain mouse stem cell pluripotency has been identified by researchers at the RIKEN Omics Science Center. The finding, published in the August issue of Stem Cells (first published online July 26, 2011), points the way to advances in regenerative medicine and more effective culturing techniques for human pluripotent stem cells.
Through their capacity to differentiate into any other type of cell, embryonic stem cells (ES cells) and induced-pluripotent stem cells (iPS cells) promise a new era of cell-based treatments for a wide range of conditions and diseases. Cultivating such cells, however, commonly relies on the use of so-called gfeederh cells to maintain pluripotency in cell culture conditions. Feeder cells keep stem cells in their undifferentiated state by releasing nutrients into the culture medium, but they have the potential to introduce contamination which, in humans, can lead to serious health risks.
Previous research has shown that mouse pluripotent stem cells can be cultured without feeder cells through the addition of a cytokine called Leukemia Inhibitory Factor (LIF) to the culture media (gfeeder-freeh culture). LIF is secreted by mouse feeder cells and activates signal pathways reinforcing a stem cell regulatory network. The researchers discovered early in their investigation, however, that the amount of LIF secreted from feeder cells is much less than the amount needed to maintain pluripotency in feeder-free conditions. This points to other, as-of-yet unknown contributing factors.
To clarify these factors, the research group analyzed differences in gene expression between mouse iPS cells cultured on feeder cells and those cultured in feeder-free (LIF treated) conditions. Their results revealed 17 genes whose expression level is higher in feeder@conditions. To test for possible effects on pluripotency, they then selected 7 chemokines (small proteins secreted by cells) from among these candidates and overexpressed them in iPS cells grown in feeder-free conditions. They found that one chemokine in particular, CC chemokine ligand 2 (CCL2), enhances the expression of key pluripotent genes via activation of a well-known signal pathway known as Jak/Stat3.
While CCL2 is known for its role in recruiting certain cells to sites of infection or inflammation, the current research is the first to demonstrate that it also helps maintain iPS cell pluripotency. The findings also offer broader insights applicable to the cultivation of human iPS/ES cells, setting the groundwork for advances in regenerative medicine.
For more information, please contact:
RIKEN is Japanfs flagship research institute devoted to basic and applied research. Over 2500 papers by RIKEN researchers are published every year in reputable scientific and technical journals, covering topics ranging across a broad spectrum of disciplines including physics, chemistry, biology, medical science and engineering. RIKENfs advanced research environment and strong emphasis on interdisciplinary collaboration has earned itself an unparalleled reputation for scientific excellence in Japan and around the world.
About the Omics Science Center
Omics is the comprehensive study of molecules in living organisms. The complete sequencing of genomes (the complete set of genes in an organism) has enabled rapid developments in the collection and analysis of various types of comprehensive molecular data such as transcriptomes (the complete set of gene expression data) and proteomes (the complete set of intracellular proteins). Fundamental omics research aims to link these omics data to molecular networks and pathways in order to advance the understanding of biological phenomena as systems at the molecular level.
Here at the RIKEN Omics Science Center, we are developing a versatile analysis system, called the gLife Science Accelerator (LSA)h, with the objective of advancing omics research. LSA is a multi-purpose, large-scale analysis system that rapidly analyzes molecular networks. It collects various genome-wide data at high throughput from cells and other biological materials, comprehensively analyzes experimental data, and thereby aims to elucidate the molecular networks of the sample. The term gacceleratorh was chosen to emphasize the strong supporting role that this system will play in supporting and accelerating life science research worldwide.
Joining forces for immune research
13.08.2018 | Max-Delbrück-Centrum für Molekulare Medizin in der Helmholtz-Gemeinschaft
The “TRiC” to folding actin
10.08.2018 | Max-Planck-Institut für Biochemie
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.
Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...
If certain signaling cascades are misregulated, diseases like cancer, obesity and diabetes may occur. A mechanism recently discovered by scientists at the Leibniz- Forschungsinstitut für Molekulare Pharmakologie (FMP) in Berlin and at the University of Geneva has a crucial influence on such signaling cascades and may be an important key for the future development of therapies against these diseases. The results of the study have just been published in the prestigious scientific journal 'Molecular Cell'.
Cell growth and cell differentiation as well as the release and efficacy of hormones such as insulin depend on the presence of lipids. Lipids are small...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
13.08.2018 | Physics and Astronomy
13.08.2018 | Physics and Astronomy
13.08.2018 | Physics and Astronomy