A research team has discovered a new mechanism for cell fate determination -- how one cell, the daughter, becomes dramatically different from the mother, even though they have the same genetic material. The study shows why mothers and daughters differ in how they express their genes.
The results of this research will be published in the Aug. 19 issue of the journal PLoS Biology.
By studying yeast, whose entire genome is known, scientists can learn the basics of cell division and apply that knowledge to the human system. Many of the fundamental mechanisms for cell division in yeast are conserved, or very similar, in mammals; many of the proteins involved in human disease are related to proteins that are involved in yeast cell division.
The new knowledge about cell fate determination could lead to a better understanding of healthy human cells, what goes awry in cancer cells and how human stem cells and germ cells work.
"Cancer may reflect a partial and aberrant loss of differentiated character, in which cells that were formerly specified to perform a specific task 'forget' that, and become more like the rapidly dividing stem cells from which they came," said Eric L. Weiss, assistant professor of biochemistry, molecular biology and cell biology in Northwestern's Weinberg College of Arts and Sciences. Weiss led the research team, which included scientists from the Massachusetts Institute of Technology.
"Understanding how differentiated states are specified might help us figure out how to remind cancer cells to go back to their original tasks or fates -- or, more likely, die."
When a yeast cell divides it produces a mother cell and a smaller, different daughter cell. The daughter cell is the one that actually performs the final act of separation, cutting its connection to the mother cell. And the daughter takes longer than the mother to begin the next cycle of division, since it needs time to grow up.
The key to the researchers' discovery of how this differentiation works is the gene regulator Ace2, a protein that directly turns genes on. The researchers found that the protein gets trapped in the nucleus of the daughter cell, turning on genes that make daughter different from mother.
The team is the first to show that the regulator is trapped because a signaling pathway (a protein kinase called Cbk1) turns on and blocks Ace2 from interacting with the cell's nuclear export machinery. Without this specific block, the machinery would move the regulator out of the nucleus, and the daughter cell would be more motherlike -- not as different.
"Daughter-cell gene expression is special, and now we know why," said Weiss.
The researchers also found that the differentiation of the mother cell and daughter cell -- this trapping of the regulator in the daughter nucleus -- occurs while the two cells are still connected.
Megan Fellman | EurekAlert!
The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung
A sudden drop in outdoor temperature increases the risk of respiratory infections
11.01.2017 | University of Gothenburg
For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.
According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
23.01.2017 | Health and Medicine
23.01.2017 | Physics and Astronomy
23.01.2017 | Process Engineering