Nav: Home

Stop or go: The cell maintains its fine motility balance with the help of tropomodulin

February 17, 2020

In a healthy cell, there is a fine balance between the protrusive structures that make the cell more migratory and the contractile structures that maintain the cell's shape and its association with the environment. A disturbance in this balance leads to several diseases, such as invasive cancers.

The most important component of both protrusive and contractile machineries is a protein called actin. This means that the proper distribution of actin between these structures is essential for the normal function of the cell. Nevertheless, the mechanisms that ensure that actin is distributed correctly between the protrusive and contractile machineries have remained elusive.

Researchers at the University of Helsinki, Finland, and the University of Pennsylvania, Philadelphia, USA, have now identified a protein called tropomodulin as a key player that maintains the balance between the protrusive and contractile actin-filament machineries within a cell.

The function of tropomodulin has previously been studied mainly in the context of muscles, where it maintains the architecture of actin filaments within the contractile fibers of muscle cells.

"We have now revealed that tropomodulins stabilise the actin filaments of the contractile structures in non-muscle cells through interacting with specific proteins within these actin filament bundles. The depletion of tropomodulins led to a loss of contractile structures, accompanied by an excess of protrusive structures, and thus to severe problems in a cell's shape and force production," says Academy Professor Pekka Lappalainen from the HiLiFE - Institute of Biotechnology, University of Helsinki.

Researchers were surprised to see that the depletion of one protein can have such drastic effects on the balance of the actin machinery.

"Another exciting and unexpected finding of this study was the notion that the same protein can have a different function depending on the tissue or cell type. Our study also sheds light on why abnormal levels of tropomodulin are linked to the progression of various cancers," says PhD student Reena Kumari.
-end-


University of Helsinki

Related Protein Articles:

A direct protein-to-protein binding couples cell survival to cell proliferation
The regulators of apoptosis watch over cell replication and the decision to enter the cell cycle.
A protein that controls inflammation
A study by the research team of Prof. Geert van Loo (VIB-UGent Center for Inflammation Research) has unraveled a critical molecular mechanism behind autoimmune and inflammatory diseases such as rheumatoid arthritis, Crohn's disease, and psoriasis.
Resurrecting ancient protein partners reveals origin of protein regulation
After reconstructing the ancient forms of two cellular proteins, scientists discovered the earliest known instance of a complex form of protein regulation.
Sensing protein wellbeing
The folding state of the proteins in live cells often reflect the cell's general health.
Protein injections in medicine
One day, medical compounds could be introduced into cells with the help of bacterial toxins.
Discovery of an unusual protein
Scientists from Bremen discover an unusual protein playing a significant role in the Earth's nitrogen cycle.
Protein aggregation: Protein assemblies relevant not only for neurodegenerative disease
Amyloid fibrils play a crucial role in neurodegenerative illnesses. Scientists from Heinrich Heine University Düsseldorf (HHU) and Forschungszentrum Jülich have now been able to use cryo-electron microscopy (cryo-EM) to decode the spatial structure of the fibrils that are formed from PI3K SH3 domains - an important model system for research.
Old protein, new tricks: UMD connects a protein to antibody immunity for the first time
How can a protein be a major contributor in the development of birth defects, and also hold the potential to provide symptom relief from autoimmune diseases like lupus?
Infection-fighting protein also senses protein misfolding in non-infected cells
Researchers at the University of Toronto have uncovered an immune mechanism by which host cells combat bacterial infection, and at the same time found that a protein crucial to that process can sense and respond to misfolded proteins in all mammalian cells.
Quorn protein builds muscle better than milk protein
A study from the University of Exeter has found that mycoprotein, the protein-rich food source that is unique to Quorn products, stimulates post-exercise muscle building to a greater extent than milk protein.
More Protein News and Protein 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

Climate Mindset
In the past few months, human beings have come together to fight a global threat. This hour, TED speakers explore how our response can be the catalyst to fight another global crisis: climate change. Guests include political strategist Tom Rivett-Carnac, diplomat Christiana Figueres, climate justice activist Xiye Bastida, and writer, illustrator, and artist Oliver Jeffers.
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

Speedy Beet
There are few musical moments more well-worn than the first four notes of Beethoven's Fifth Symphony. But in this short, we find out that Beethoven might have made a last-ditch effort to keep his music from ever feeling familiar, to keep pushing his listeners to a kind of psychological limit. Big thanks to our Brooklyn Philharmonic musicians: Deborah Buck and Suzy Perelman on violin, Arash Amini on cello, and Ah Ling Neu on viola. And check out The First Four Notes, Matthew Guerrieri's book on Beethoven's Fifth. Support Radiolab today at Radiolab.org/donate.