Cell sensing and movement (Introduction)
by David Turell , Wednesday, October 29, 2014, 14:06 (3678 days ago)
Moving toward an attractant, making more actin:-http://www.the-scientist.com//?articles.view/articleNo/41346/title/Cellular-Chemotaxis/
Cell sensing and movement
by David Turell , Tuesday, February 20, 2018, 02:03 (2468 days ago) @ David Turell
Cells sense inadequate blood supply through a gene just discovered:
https://medicalxpress.com/news/2018-02-newly-gene-blood-vessels.html
"A new study published today found that a newly discovered gene helps grow blood vessels when it senses inadequate blood flow to tissues.
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"Dr. Marsden's lab studies endothelial cells, the cells that line the inside of blood vessels. For this study they looked at a newly described group of genes called long non-coding RNAs, or lncRNAs. RNA, or ribonucleic acid, is found in all cells and it has traditionally been thought that its main job was to carry instructions from genes in DNA to make proteins. But lncRNAs have other roles, including determining the eventual function that individual cells will play in an organism. Studying lncRNAs gives researchers opportunities to find new markers and tests to help make diagnoses for patients.
"Dr. Man said this study was the first to identify which lncRNAs are more enriched with endothelial cells compared to other cell types. They plan to make the list public for other researchers to use.
"They then discovered that one of those lncRNAs, called STEEL (for spliced-transcript endothelial-enriched lncRNA) was the one that sensed inadequate blood flow in microscopic blood vessels.
"'What is really interesting is that STEEL helps our body respond to inadequate blood flow by growing more blood vessels," Dr. Man said.
"'These results show that our bodies are really finely tuned to perform, just as we need them to, and also demonstrate that disruptions to this fine balance can cause problems. This data can be used to improve our understanding of blood vessel diseases and help us find ways to improve healing and recovery after injury."
"This study also made some findings that could be helpful for researchers studying lncRNAs in general, Dr. Marsden said. This study is one of the early studies to assess on a large scale which and how many proteins can associate with an individual lncRNA. "
Comment: Obviously endothelial cells can sense low blood flow and then activate the proper gene to grow more vessels in the area. This purposeful activity certainly looks designed.
Cell sensing and movement
by David Turell , Tuesday, February 27, 2018, 15:37 (2461 days ago) @ David Turell
Fat cells can move and help in repair of a wound, seen in fruit flies:
https://cosmosmagazine.com/biology/fat-cells-swim-and-block-wounds
"At least in fruit flies, fat cells have been found to exhibit several previously unknown and surprising behaviours geared to healing wounds and fending off infection.
"The behaviours are surprising because they involve properties that fat cells – considered to be one of the most uncontroversial, best examined and, frankly, unexciting cell types around – had not been remotely suspected of possessing.
"The cells, it turns out, can swim – really swim, moving along by flexing and contracting. What’s more, they do so in response to some form of unknown signal – something that has so far eluded the scientists searching for it.
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"The fat cells can be seen propelling themselves forward, using wave-like contortions, towards the site of the injury. This is doubly interesting. Until now, fat cells were not thought to be capable of moving under their own power, nor were they thought to play any role at all in wound repair.
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"Martin and his colleagues filmed the fat cells moving directly to the wound site and bunching up within it, sealing it off from the outside. At the same time, they cause debris from the opening to be wafted away from the critical zone, into the waiting maws of immune system cells.
"The fat cells then remained at the wound until healing was complete, at which point they detached and swam away.
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“We had to be sure that they weren’t just drifting and then sort of sticking at the wound site,” says Martin. “And we had to rule out that they weren’t just being sort of sucked to the wound by fluid coming out of the hole, much like if you tossed a flannel in a bath and then took the plug out.”
"To do so, they genetically engineered fruit fly fat cells that lacked the actin and myosin fibres, and then repeated the experiment. The modified cells didn’t move at all, indicating that the “natural” versions were indeed actively migrating.
"How the cells “know” to move to a wound is unknown, but Martin and his colleagues have ruled out the possibility that they are responding to signals sent by the immune system. The fat cells, they established, still move towards wounds even if immune cells aren’t present.
"Once at the site, however, in normal fruit flies, the two cell types clearly collaborate.
“So fat cells and immune cells probably are important as a team, both in a healthy situation, like healing a wound, and in a pathology situation, like cancer,” he says.
Comment: My interpretation is that these fat cells are programmed to act in this purposeful manner and how they 'know' where to go is from a still to be discovered molecular signal which hey the swim and follow. I can predict dhw's answer to this.
Cell sensing and movement
by dhw, Wednesday, February 28, 2018, 14:03 (2460 days ago) @ David Turell
DAVID’s comment: My interpretation is that these fat cells are programmed to act in this purposeful manner and how they 'know' where to go is from a still to be discovered molecular signal which hey the swim and follow. I can predict dhw's answer to this.
Your own hypothesis that 3.8 billion years ago your God preprogrammed fat cells to come into existence and automatically act purposefully and cooperatively in obedience to some unknown preprogrammed molecular signal is, I’m afraid, equally predictable. But I don’t want to disappoint you. Such behaviour is astonishingly reminiscent of the way ants cooperate in dealing with threats. Funnily enough, many of our fellow animals and even we humans cooperate in similar ways. Anyone would think they and we were intelligent. But maybe they and we only appear to be intelligent.
Under “Biomimetics”:
DAVID: A very brief excerpt with a picture of the way the beetles look like the leaf injury from their bites:
https://www.newscientist.com/article/2162276-beetles-hide-by-looking-like-the-bite-mark...
DAVID’s comment: I'm too cheap to buy the article, but look at the picture to make the point. How does an evolutionary process do this? Not by chance.
Agreed. Presumably you think your God preprogrammed this 3.8 billion years ago, or did a quick dabble. Or do you think he might have given the beetle the autonomous intelligence to work it out? Anyway, thanks for another lovely “natural wonder”.
Cell sensing and movement
by David Turell , Thursday, March 01, 2018, 00:50 (2459 days ago) @ dhw
DAVID’s comment: My interpretation is that these fat cells are programmed to act in this purposeful manner and how they 'know' where to go is from a still to be discovered molecular signal which hey the swim and follow. I can predict dhw's answer to this.
dhw: Your own hypothesis that 3.8 billion years ago your God preprogrammed fat cells to come into existence and automatically act purposefully and cooperatively in obedience to some unknown preprogrammed molecular signal is, I’m afraid, equally predictable. But I don’t want to disappoint you. Such behaviour is astonishingly reminiscent of the way ants cooperate in dealing with threats. Funnily enough, many of our fellow animals and even we humans cooperate in similar ways. Anyone would think they and we were intelligent. But maybe they and we only appear to be intelligent.
I know only they only appear intelligent and we are. See today's entry on homeostasis and automaticity in bacteria.
Under “Biomimetics”:
DAVID: A very brief excerpt with a picture of the way the beetles look like the leaf injury from their bites:
https://www.newscientist.com/article/2162276-beetles-hide-by-looking-like-the-bite-mark...DAVID’s comment: I'm too cheap to buy the article, but look at the picture to make the point. How does an evolutionary process do this? Not by chance.
dhw: Agreed. Presumably you think your God preprogrammed this 3.8 billion years ago, or did a quick dabble. Or do you think he might have given the beetle the autonomous intelligence to work it out? Anyway, thanks for another lovely “natural wonder”.
The beetles didn't find the mutations to do it. And a hunt and peck attempt would not have meant survival.