Physical force alone spurs gene expression, study reveals | Hacker News Reader

Physical force alone spurs gene expression, study reveals

phys.org

123 pointspseudolus26 comments

"We found that force can activate genes without intermediates, without enzymes or signaling molecules in the cytoplasm," said University of Illinois mechanical science and engineering professor Ning Wang, who led the research. "We also discovered why some genes can be activated by force and some cannot."

That's a bad headline. It implies that nothing else influences gene expression, when the article says that physical stretching of force-sensitive histones can influence gene expression, without the assistance of any other factors.

To be clear, factors other than physical force can also influence gene expression.

>when the article says that

"study reveals"

>physical stretching of force-sensitive histones

"physical force"

>can influence gene expression,

"spurs gene expression"

>without the assistance of any other factors

"alone"

Meaning the of conveyed sentences is order words of also by the the.

In this case it's not about the order of the words, but your interpretation of the meaning of "alone." Read the headline as it is, a news headline (rather than a scientific conclusion), and it might make more sense.

Ambiguity is less tolerable in journalism than it may be in other media.

A good sentence can be a bad headline.

It's the same principle as Murphy's Law in engineering. If it can be interpreted in a different way, you don't put it at the top of your story.

In this case, removing the word "alone" makes a better headline.

The meaning of sentences is also influenced by the space of what they might possibly mean. While you're correct that the headline, interpreted according to the normal rules of English, implies that nothing other than physical force can affect gene expression, this interpretation is easily ruled out by the fact that it's impossible. It's not a long stretch to the intended meaning.

The intended meaning was obvious to me, fwiw. I think the "alone" also adds emphasis to the key discovery.

"He alone is capable of pulling the sword from the stone."

Does this imply he can pull the sword from the stone by himself or that only he can pull the sword from the stone?

Only he can.

He can do this alone = he can do it without help He alone can do this = no one but him can do it

How about "ARM STRENGTH alone is capable of pulling the sword from the stone."

Does that mean that your leg muscles (which are stronger) are NOT capable of pulling the sword? Does that mean a tractor can't do it?

Article is here: https://advances.sciencemag.org/content/6/14/eaay9095

Earlier work is described in the U of I press release: https://mechanical.illinois.edu/news/force-triggers-gene-exp... and available to read here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5121013/

Glad that none of the work was behind paywall!

> Force-induced gene up-regulation does not follow the weak power law but depends on H3K9 demethylation

I'm sure it's common knowledge to people inside the field, but "The weak power law" is quite vague for non-experts.

From the article I got this:

> In this study, we reveal that high force frequency (>50 Hz) does not induce rapid transcription, although the chromatin is being stretched to sufficient extents to allow for transcription. Over the last two decades, studies on the rheological responses of living cells demonstrate that living cells exhibit a gradual stiffening response to increasing force frequencies [i.e., the weak power law (12, 27)].

Ok, that doesn't really clarify that much for me. Is it the (weak power) law or the weak (power law), for example? I mean we're talking about exerting force, both kind of could make sense.

Any experts willing to explain a bit?

You got me curious. Apparently it's "weak power-law" and means a power-law relationship only applies over part of the range. As opposed to strong power law which applies over the full curve, or false power law where only a truncated part of the data fits a power law.

Different types of power laws: https://arxiv.org/pdf/1507.03408.pdf

Power-law rheology of cells: https://www.annualreviews.org/doi/pdf/10.1146/annurev-matsci...

Thank you for looking it up!

Wondering how this ties into epigenetics.

mount -o remount,rw /dev/dna /neurologicalsubsystem

Interesting.

So a nice punch in the face or a swift kick in the ass is not enough to produce brain reprogramming. Frequency matters.

I have to test this out on my brother.

Well, to be more accurate: they are saying that proteins get created in response to physical force. These don't necessarily "reprogram the brain." It's just that punching your brother in the arm will result in a localized response long before the chemical response arrives from other organs in response to the brain's signals of pain.

> So a nice punch in the face or a swift kick in the ass is not enough to produce brain reprogramming.

I know this is a comment supposedly made in jest, but a) anyone who has been through a single traumatic event that took ages to unlearn can tell you otherwise and b) domestic violence isn't funny.

Considering that the primary force on my body is gravity, I wonder whether these gene expression mechanisms underlie weight control...or rather more specifically, my body's stubborn refusal to change weight downward.

There is some research on this. I'll try and find an article I read about it a while ago.

Here it is: "Body weight homeostat that regulates fat mass independently of leptin in rats and mice" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5777058/

It's different than exactly what you were talking about, but the idea of "gravitostat" is interesting so I thought I'd still add it.

Thanks! I also read this study a year or ago or so, thanks for reminding me.

I’m curious how biologists thought callouses formed before this research? Magic?

> I’m curious how biologists thought callouses formed before this research? Magic?

The answer wasn't really known, and the knowledge of this mechanism didn't really exist. This release also doesn't specifically address calluses, though past research (e.g. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2133....) doesn't quite result in a definitive hypothesis either. Could be mechanical, or could be the body's response to damage to specific cells or structures in the skin.

(I may have misstated the above. A dermatologist or other researcher focusing on skin will likely have a more accurate answer than what I could dig up.)

P.s. cynicism is generally appreciated in science, but derision... not so much.

Wow tough crowd!

It was thought they were formed via responses to e.g. damage-signalling molecules cells might release.

This article is about cells deciding to express genes on their own, via force, independent of any chemicals that other cells might be releasing around them.

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