Nav: Home

Untangling the knots in cell stress

May 12, 2017

Kyoto, Japan -- How do cells correctly make proteins?

Part of the answer lies in quality control for newly-minted proteins, which takes place in the sub-cellular compartments of the 'endoplasmic reticulum', or ER. An over-burdened -- or 'stressed' -- ER can result in proteins becoming disorganized, a condition which cells seek to rectify by undertaking 'unfolded protein response', or UPR.

During this reorganization, 'UPR transducers' in the ER sort the proteins for correction. Humans are known to have ten types of these transducers, but for years, scientists have not been able to explain why so many varieties are needed for the process to work.

Now in an article published in the Journal of Cell Biology, Tokiro Ishikawa and Kazutoshi Mori of Kyoto University describe how different UPR transducers are used selectively, depending on the developmental stage of the cell and the type of stress.

"We started by looking for proteins that cause ER stress during the development of medaka fish embryos, which are known to have the same ten transducers," explains first author Ishikawa.

"We found that at first the production of short chain collagen causes a certain transducer to be activated for quality control." Collagen is the most abundant protein in vertebrates, providing external support for cells.

In the next stage of development, cells received a signal from main actor proteins and started to produce longer-chain collagen. In response to this new ER stress, a new UPR transducer was activated to produce components to export the larger collagen out of the ER. Without this, larger collagen would be unable to leave the cells and do its job.

"This showed us that different UPR transducers are activated to cope with different ER stresses caused by different proteins," says Ishikawa.

Senior researcher Mori continues, "We see UPR working 'backstage', so to speak, to support the main actors during cell differentiation and thereby orchestrating various biological processes"

The team is next seeking to understand how cells discriminate between lengths of collagen to activate different transducers, further deepening understanding of UPR's role in cellular processes and development.
-end-
The paper "UPR Transducer BBF2H7 Allows Export of Type II Collagen in a Cargo- and Developmental Stage-Specific Manner" appeared 12 May 2017 in the Journal of Cell Biology, with doi: 10.1083/jcb.201609100

Kyoto University is one of Japan and Asia's premier research institutions, founded in 1897 and responsible for producing numerous Nobel laureates and winners of other prestigious international prizes. A broad curriculum across the arts and sciences at both undergraduate and graduate levels is complemented by numerous research centers, as well as facilities and offices around Japan and the world. For more information please see: http://www.kyoto-u.ac.jp/en

Kyoto University

Related Stress Articles:

How do our cells respond to stress?
Molecular biologists reverse-engineer a complex cellular structure that is associated with neurodegenerative diseases such as ALS
How stress remodels the brain
Stress restructures the brain by halting the production of crucial ion channel proteins, according to research in mice recently published in JNeurosci.
Why stress doesn't always cause depression
Rats susceptible to anhedonia, a core symptom of depression, possess more serotonin neurons after being exposed to chronic stress, but the effect can be reversed through amygdala activation, according to new research in JNeurosci.
How plants handle stress
Plants get stressed too. Drought or too much salt disrupt their physiology.
Stress in the powerhouse of the cell
University of Freiburg researchers discover a new principle -- how cells protect themselves from mitochondrial defects.
Measuring stress around cells
Tissues and organs in the human body are shaped through forces generated by cells, that push and pull, to ''sculpt'' biological structures.
Cellular stress at the movies
For the first time, biological imaging experts have used a custom fluorescence microscope and a novel antibody tagging tool to watch living cells undergoing stress.
Maternal stress at conception linked to children's stress response at age 11
A new study published in the Journal of Developmental Origins of Health and Disease finds that mothers' stress levels at the moment they conceive their children are linked to the way children respond to life challenges at age 11.
A new way to see stress -- using supercomputers
Supercomputer simulations show that at the atomic level, material stress doesn't behave symmetrically.
Beware of evening stress
Stressful events in the evening release less of the body's stress hormones than those that happen in the morning, suggesting possible vulnerability to stress in the evening.
More Stress News and Stress Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Reinvention
Change is hard, but it's also an opportunity to discover and reimagine what you thought you knew. From our economy, to music, to even ourselves–this hour TED speakers explore the power of reinvention. Guests include OK Go lead singer Damian Kulash Jr., former college gymnastics coach Valorie Kondos Field, Stockton Mayor Michael Tubbs, and entrepreneur Nick Hanauer.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at Radiolab.org/donate.