autonomy v. automaticity: single cell regeneration (Evolution)

by David Turell , Thursday, April 05, 2018, 18:45 (2203 days ago) @ David Turell

A large single celled organism can regenerate if cut in half. Each half regenerates the other half automatically using an enzyme system run by its genome:

https://phys.org/news/2018-04-reveals-unicellular.html

"In a new study, published in Current Biology this week, a research team from Uppsala University in Sweden reports new insights into the regenerative capabilities of Stentor, a single celled model organism for regeneration biology. The study used novel gene expression methods that allowed the researchers to identify over one thousand genes that are involved in the regeneration process of individual stentor cells.

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" Now, a research team from Uppsala University has identified over 1000 genes involved in rebuilding a fully-fledged Stentor cell cut into two halves.

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"Stentor cells have a distinct shape, with a mouth part to eat bacteria on one side, and a tail that attaches to particles on the other side. Previous studies showed that if you cut a Stentor cell in half, each cell fragment will regenerate into a fully functional cell with a mouth and tail. This means that one half needs to regrow a mouth, while the other half has to regenerate a tail. Using a new method, the Uppsala researchers were able to identify which Stentor genes were involved in regenerating a new mouth, and which genes were responsible for building a new tail.

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"Using the newly developed protocol, Onsbring found that many more genes are involved in the regeneration of the mouth part as compared to the tail of the cell. "The mouth part of the cell is used for feeding and represents a rather large and complex structure. Our results indicate that rebuilding this mouth structure involves roughly ten times as many genes as compared to regenerating the tail part of the cell," says Onsbring. "We also managed to confirm observations from previous microscopy studies that suggested that cellular regeneration shares similarities with the process of cell division. We found that several genes that were previously implicated in cell division were also upregulated during various stages of regeneration." (my bold)

"Finally, the Uppsala research team also identified a group of signaling proteins, known as proteins kinases, to be involved in cellular regeneration of stentor cells. "A previous study had recently reported that the Stentor genome encodes many of these proteins kinase genes. The function of this expanded set of genes was still unclear however. If anything, we now show that many of these protein kinases are expressed during specific stages of the regeneration process. Possibly, the expansion of this group of signaling genes represented an important evolutionary step in the emergence of the ability to perform self-repair," concludes Ettema."

Comment: Note my bold. The genome has the information for repair control. The genes are spread throughout the organism and each half gets stimuli which tells it the other half is missing and reacts automatically enlisting a group of complex enzymes to take control. No evidence any thought/intelligence need be involved, but, yes, the activity looks intelligent.