OCT 16, 2021 1:32 AM PDT

Microtubules Found to Act as Mechanosensors

WRITTEN BY: Carmen Leitch

As organisms grow, live, and move through the world, they're subjected to an array of internal and external forces. Biological forms must be able to withstand the stresses of stretching and compression down to the cellular level. Mechanical forces are thought to have a significant impact on the growth, development, and health of cells and tissues.

Cells need a sturdy but flexible framework called a cytoskeleton to give them structural integrity. To perform all the functions that might be required of it, a cell also has to have the ability to move things around the cell. Cellular components called microtubules help perform both functions; they make up part of the cytoskeleton, and they also play a critical role in intracellular transport by acting as a kind of rail network. Motor proteins called kinesin and dynein shuttle things on this microtubule network using molecular fuel called ATP to power their movement. Microtubules are dynamic too; they can grow, shrink, bend, and flex with compression, stretching, and movement.

Now researchers have shown that microtubules can also function as a kind of mechanosensor that can pick up on the state of the cell and adjust transport in the cell accordingly.

Microtubules may function as mechanosensors to regulate the intracellular transport of kinesin. Tension, flex, or compression in the microtubule slowed down the movement of kinesis along the microtubule due to increased intermolecular interaction, demonstrated by a molecular dynamics simulation / Credit: Syeda Rubaiya Nasrin, Christian Ganser, et al. Science Advances 2021

In this study, the researchers used atomic force microscopy and a cell-free model in which they observed individual kinesin motor proteins as they migrated along microtubules that were maintained on a lipid bilayer. The microtubules were kept straight or bent to study how the speed of the kinesin proteins changed under the different conditions, as shown in this the video. When microtubules are bent, the kinesin proteins don't move as quickly. The variability in the speed is illustrated in the image. It had been thought that kinesin gets slower because of cracks or holes in the microtubule structure, but the researchers found that the slowdown occurs even there are no cracks.

Image credit: Pixabay

The research, which has been reported in Science Advances, suggested that the kinesin proteins seem to stick to the bent microtubules more than they do to straight microtubules. A molecular simulation indicated that the deformed units of microtubules have a greater interaction energy with kinesin, revealing how the conformation of microtubules can regulate the movement of these motor proteins.

This work, which was completed by an international team of researchers, could have implications for biomechanics, biosensors, research that involves the mechanical forces that occur inside and outside of cells, diseases related to intracellular transport or the cytoskeleton.

Sources: Hokkaido University, Science Advances

About the Author
BS
Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
OCT 18, 2022
Immunology
T Cell Deficiency Leaves Some Vulnerable to Infection
OCT 18, 2022
T Cell Deficiency Leaves Some Vulnerable to Infection
The mycobacterium avium complex (MAC) bacteria can be found everywhere, so almost everyone breathes some of it in occasi ...
OCT 18, 2022
Genetics & Genomics
Mitochondrial DNA Can Move to the Genome to Trigger Human Evolution
OCT 18, 2022
Mitochondrial DNA Can Move to the Genome to Trigger Human Evolution
Mitochondria are often called the powerhouse of the cell, and these organelles are well-known for their energy-generatin ...
OCT 25, 2022
Cell & Molecular Biology
Liver Disease Discovery Resolves Controversy
OCT 25, 2022
Liver Disease Discovery Resolves Controversy
Liver diseases are a serious health problem. Chronic liver disease is estimated to impact over 1.5 billion people.
OCT 26, 2022
Genetics & Genomics
Ancient Selfish Genes Carried by Yeast May Change Our View of Evolution
OCT 26, 2022
Ancient Selfish Genes Carried by Yeast May Change Our View of Evolution
When genes are passed down to the next generation, some have an advantage, and are more likely to be inherited than othe ...
NOV 06, 2022
Genetics & Genomics
The Lone Participant in a CRISPR Therapy Trial has Died
NOV 06, 2022
The Lone Participant in a CRISPR Therapy Trial has Died
In August of this year, a single patient was enrolled in a trial that used CRISPR to correct a genetic mutation that led ...
NOV 21, 2022
Cell & Molecular Biology
New Insights Into Parkinson's Pathology & A Drug Candidate
NOV 21, 2022
New Insights Into Parkinson's Pathology & A Drug Candidate
Over six million people have Parkinson's disease, and more are diagnosed every day. The neurodegenerative disease is cha ...
Loading Comments...