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:

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.
How plants cope with stress
With climate change comes drought, and with drought comes higher salt concentrations in the soil.
Gene which decreases risk of social network-related stress, increases finance-related stress risk
Researchers have discovered that the same gene which increases your risk of depression following financial stress as you grow older also reduces your chance of depression associated with friendship and relationships stresses when young- your social network.
Innate stress
A team of researchers from the Higher School of Economics and the RAS Vavilov Institute of General Genetics has been able to statistically monitor the impact of the monoamine oxidase A gene (MAOA) on the subjective evaluation of well-being among men.
Is a stress shot on the horizon?
Rats immunized weekly for three weeks with beneficial bacteria showed increased levels of anti-inflammatory proteins in the brain, more resilience to the physical effects of stress, and less anxiety-like behavior.
More Stress News and Stress Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Rethinking Anger
Anger is universal and complex: it can be quiet, festering, justified, vengeful, and destructive. This hour, TED speakers explore the many sides of anger, why we need it, and who's allowed to feel it. Guests include psychologists Ryan Martin and Russell Kolts, writer Soraya Chemaly, former talk radio host Lisa Fritsch, and business professor Dan Moshavi.
Now Playing: Science for the People

#538 Nobels and Astrophysics
This week we start with this year's physics Nobel Prize awarded to Jim Peebles, Michel Mayor, and Didier Queloz and finish with a discussion of the Nobel Prizes as a way to award and highlight important science. Are they still relevant? When science breakthroughs are built on the backs of hundreds -- and sometimes thousands -- of people's hard work, how do you pick just three to highlight? Join host Rachelle Saunders and astrophysicist, author, and science communicator Ethan Siegel for their chat about astrophysics and Nobel Prizes.