SMC proteins can reverse direction, reshaping DNA and solving key scientific debates. This discovery could impact research on gene-linked diseases.
Scientists from Delft, Vienna, and Lausanne have uncovered that the protein machines responsible for shaping our DNA can reverse their direction.
Previously, it was believed that these SMC motors, which create loops in DNA, could only move in a single direction. This groundbreaking discovery, published in Cell, provides crucial insights into how these motors organize our genome and regulate gene activity.
Connecting DNA
“Sometimes, a cell needs to be quick in changing which genes should be expressed and which ones should be turned off, for example in response to food, alcohol, or heat. To turn genes off and on, cells use Structural Maintenance of Chromosomes (SMC) motors that act like switches to connect different parts of DNA,” first author Roman Barth explains.
“However, SMC machines don’t naturally know which parts to connect. They simply load somewhere on the DNA and start shaping it into a loop until they reach a point where they are forced to stop. That’s why they rely heavily on the ability to explore both sides of the DNA to find the right stop signs.”
Gearbox
Biophysicists at Delft University of Technology now found that SMC motors can switch direction, contrary to what was thought to be possible.
“Our experiments show that SMCs momentarily pull DNA from one side, and then switch direction to pull DNA from the opposite side. By doing so, they can pull DNA into a loop from both sides over time. We found this to be true for all types of SMC motors, of which there are many,” Delft professor Cees Dekker, who supervised the research, says.
“You can compare it to a gearbox in a car: With a manual gear stick, you can let the car move forward or backward. We even identified the ‘gear lever’, protein subunit NIPBL, in the cohesin SMC motor protein.”
Impressive nanotechnology
To discover the reverse gear of SMC motors, the researchers used an advanced home-built microscope to look at single proteins on individual DNA molecules.
That in itself is an impressive achievement, as Barth explains: ”A single cell contains millions of proteins and the human body is made of trillions of cells. Pulling out a few proteins and being able to ‘watch’ them one by one is a remarkable feat of nanotechnology that involves imaging at a scale of nanometres – 100,000 smaller than the width of a human hair.”
Neurodegenerative diseases
“Once we understand how SMC molecular motors shape DNA, we may start asking what goes wrong in diseases like cancer and neurogenerative diseases, and importantly, how to correct it,” says Barth.
“Neurogenerative diseases for example can be the result of misregulated genes during early stages of pregnancy. In fact, there are a couple of severe diseases, such as Cornelia de Lange syndrome, linked to SMCs, where the motors likely fail to switch correctly inside the cells of the embryo.”
Science in action
The study finally resolves the confusion in the scientific community about various contradictory theories on how SMCs work. Early research suggested that SMCs can strictly move in one direction only, while other research suggested that they pulled in DNA from both sides simultaneously. The discovery resolves these controversies.
Barth: “Having found commonalities among SMC motors helps to focus and streamline the SMC research field. We don’t have to look for a new mechanism for every individual type of SMC protein anymore. It will also accelerate the field of applied science. I would be glad to see this knowledge move into pharma companies, hospitals, and eventually doctors’ offices.”
Reference: “SMC motor proteins extrude DNA asymmetrically and can switch directions” by Roman Barth, Iain F. Davidson, Jaco van der Torre, Michael Taschner, Stephan Gruber, Jan-Michael Peters and Cees Dekker, 16 January 2025, Cell.
DOI: 10.1016/j.cell.2024.12.020
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7 Comments
Jesus Christ is the creator of everything including our DNA. The evidence of a designer in our DNA is so clear if we are honest. Jesus holds the whole universe together by the His Word and power. All praise to Him.
We are living in 2025 and people are still obsessed with the Fake Jesus Story. The Bible isn’t like a video recording or a tape recording.
We have no proof Jesus Christ existed. He definitely didn’t create our DNA. It’s like saying Donald Duck created the Universe. If Jesus was real he would be here on Earth. But Christians tell us we don’t need to see him, in fact this makes them mad. It’s all lunacy.
Jesus never existed. It’s even possible that he was invented by Rome to pacify the Jewish population with a more “Rome friendly” messiah. There are absolutely zero references to Jesus in a time where very much was written down. If Jesus did exist, historians would have been fighting each other to write about him. It never happened.
Sigh.. He exists and existed, as various Roman documents indicate, even if you wish to ignore the Bible.
And many scholars do indeed write about him. You may choose not to believe in Him as a religious figure, but too even deny his existence is just foolishness.
I recommend you read Isaias 7:14, and 8: 1-3. where you will find the correct data about this topic. The word Betula which represents in Hebrew Virgen was never used. instead, was written ha almah to describe a young woman, young girl, which later on the prophet will
procreate with the prophetess as it was commanded by God, Chapter 8:1-3.
The Child will be named El-Inmanu which means { The announce one} and represents the same oracle found on 8: 1-3 but on this reference will be known as Mahel-salas-hashbaz meaning immediate destruction. This do not represent any prophesy regarding a Savior to be fulfill seven hundred years later in Palestine
This is so amazing can’t wait to find out more explorations
When people refer to the Bible as if it is only one source, you can usually write off what comes next as uneducated. What follows will usually be stomach talk. Almost exactly like LLMs but the upvote is food or sex. Motor proteins basically demand theism once you truly investigate the level of data compression in DNA and the constraints and specificity with which proteins interact. The sad thing is this info has been available for over 40 years. YouTube throttles most high production value protein animation content and clearly promotes low value “blob model” trash done on a whiteboard.