The study was published in the July 31 issue of the Journal of Cell Biology.
The sense of top and bottom is often lost in cells that become cancerous and may be an important factor in metastasis.
Cells depend on the location of a number of proteins and lipids to recognize and maintain their polarity. Moving these lipids and proteins from where they are produced to where they are needed is a dynamic process.
Dr. Athar Chishti, professor of pharmacology at the UIC College of Medicine and principal investigator of the study, said researchers knew that a lipid called PIP3 is very important in signalling polarity. But the process everyone wanted to understand, he said, "was the trafficking and disposition of this lipid to where it was needed at the growing tips of the cells."
Chishti's research team, including Kaori Horiguchi and Dr. Toshihiko Hanada, determined that one domain of a molecular motor protein called a kinesin that they had discovered interacted with PIP3 binding protein. They showed that the kinesin and this binding protein motored the PIP3 along microtubules -- the tracks upon which the kinesins move their cargoes.
They also showed that the kinesin-binding adaptor and PIP3 were found together at the tips of the nerve cells and that in one of these cell types these molecules were most abundant in the longest extension, called the axon.
"We found the motor, the binding domains and an adaptor," said Chishti. "When the adaptor binds PIP3, it is delivered to the membrane where it is needed, and if you block this process, polarity is lost."
In some cells, like neurons, there are dramatic differences in the structure and function of the different ends of a cell. But even in cells where the difference between the ends is not as obvious, the delivery process is essential. Loss of cell polarity is often the first step in converting a normal cell to a cancer cell, Chishti said.
The discovery illuminates a key step in the trafficking and disposition of polarity determinants. Science magazine highlighted the Chishti paper as an Editor's Choice in the August 18th issue and in this week's Signal Transduction Segment online at http://stke.sciencemag.org/.
"Now we know the cargo, and we know the motor," said Chishti. "The next step will be to find out what turns the motor on and tells it to start down the track to deliver the cargo.
"In the kinesin field, there are two fundamental questions: what are the cargoes, and what turns the motors on and off that carry them."
Building a brain, cell by cell: Researchers make a mini neuron network (of two)
23.05.2018 | Institute of Industrial Science, The University of Tokyo
Research reveals how order first appears in liquid crystals
23.05.2018 | Brown University
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
23.05.2018 | Life Sciences
23.05.2018 | Life Sciences
23.05.2018 | Physics and Astronomy