Uncommon Descent Serving The Intelligent Design Community

First cell with a mitochondrion was already complex


By now, this kind of thing shouldn’t even be a surprise:

A collaborative study between the groups of Toni Gabaldón, ICREA researcher at the Institute for Research in Biomedicine (IRB Barcelona) and the Barcelona Supercomputing Center (BSC-CNS), and Berend Snel at the University of Utrecht, has concluded that the first cell to incorporate a mitochondrion (considered the key step to the increased complexity of eukaryotic cells) already presented eukaryote-like complexity in structure and functions. This scenario serves as a bridge between the signs of complexity observed in some archaeal genomes and the proposed role of mitochondria in triggering eukaryogenesis.

“The acquisition of mitochondria was considered either to be the crucial first step or the last step in the development of eukaryotic cell complexity,” explains Gabaldón. “Our findings show that it was indeed a crucial event, but that it happened in a scenario where cell complexity had already increased.”

For roughly the first half of the history of life on Earth, the only forms of life were the relatively simple cells of bacteria. “Eukaryotic cells are larger, contain more DNA and are made up of compartments, each with their own task,” explains first author Julian Vosseberg. “In that sense, you could compare bacterial cells with a tent, while eukaryotic cells are more like houses with several rooms.”

How and when organisms traded the tent for a house is still a mystery, as there are no intermediate forms. One important moment in evolution was the origin of mitochondria, a component of eukaryotic cells that function as their ‘power plants.” Mitochondria were once free-living bacteria, but during evolution, they were absorbed by the ancestors of today’s eukaryotic cells. As gene duplication probably drove the increase in cell complexity, the researchers attempted to reconstruct the evolutionary events based on these genetic changes.

Institute for Research in Biomedicine (IRB Barcelona), “Timeline of early eukaryotic evolution unveiled” at Phys.org

Paper. (paywall)

Already complex? No intermediate forms? Where have we heard that before.

Wow, that first cell must have been a doozie! All the genetic material needed to work as a prokaryote, plus all the genes needed to switch to eukaryote living, even as the prokaryotes must then have lost those same genes, and then the remaining original genes stayed true for billions of years, unused, until needed for the Cambrian explosion! Isn't that one of the stories we've been told to get around the mathematical difficulties of de-novo genes appearing throughout the ages by Darwinian means? Fasteddious
There are observed cases of prokaryotes living in amoebae and even other prokaryotes. But there isn't any evidence that prokaryotes can join and produce a eukaryote. There are more differences between the two than endosymbiosis can account for. ET
@Martin @1 You beat me to it. You must type faster than I do. (Mitochondria were once free-living bacteria, but during evolution, they were absorbed by the ancestors of today’s eukaryotic cells) It is to laugh! Belfast
A few notes:
Endosymbiosis: A Theory in Crisis by Jeffrey P. Tomkins, Ph.D. * - Oct. 30, 2015 Excerpt: However, now that genome sequencing is inexpensive and widespread, the evolutionary story of endosymbiosis has become increasingly clouded and controversial. As new bacterial and eukaryotic genomes are sequenced and the proteins they encode are deduced, the whole evolutionary idea of endosymbiosis has been thrown into utter confusion. One of the most unexpected discoveries has been the utter lack of identified genes that would support the evolutionary tale. As stated in a recent paper, "What was not anticipated was how relatively few mitochondrial proteins with bacterial homologs [sequence similarity] would group specifically with ?-Proteobacteria in phylogenetic [evolutionary tree] reconstructions: At most, only 10–20% of any of the mitochondrial proteomes examined so far display a robust ?-proteobacterial signal.4" This lack of evidence for mitochondrial genes derived from bacterial origin in both the mitochondrial DNA and the genome contained in the cell’s nucleus, where most mitochondrial genes are located, is a serious problem for the evolutionary story.,,, http://www.icr.org/article/endosymbiosis-theory-crisis Information Processing Differences Between Archaea and Eukarya—Implications for Homologs and the Myth of Eukaryogenesis by Change Tan and Jeffrey P. Tomkins on March 18, 2015 Abstract In the grand schema of evolution, a mythical prokaryote to eukaryote cellular transition allegedly gave rise to the diversity of eukaryotic life (eukaryogenesis). One of the key problems with this idea is the fact that the prokaryotic world itself is divided into two apparent domains (bacteria and archaea) and eukarya share similarities to both domains of prokaryotes while also exhibiting many major innovative features found in neither. In this article, we briefly review the current landscape of the controversy and show how the key molecular features surrounding DNA replication, transcription, and translation are fundamentally distinct in eukarya despite superficial similarities to prokaryotes, particularly archaea. These selected discontinuous molecular chasms highlight the impossibility for eukarya having evolved from archaea. In a separate paper, we will address alleged similarities between eukarya and bacteria. https://answersingenesis.org/biology/microbiology/information-processing-differences-between-archaea-and-eukarya/ Information Processing Differences Between Bacteria and Eukarya—Implications for the Myth of Eukaryogenesis by Change Tan and Jeffrey P. Tomkins on March 25, 2015 Excerpt: In a previous report, we showed that a vast chasm exists between archaea and eukarya in regard to basic molecular machines involved in DNA replication, RNA transcription, and protein translation. The differences in information processing mechanisms and systems are even greater between bacteria and eukarya, which we elaborate upon in this report. Based on differences in lineage-specific essential gene sets and in the vital molecular machines between bacteria and eukarya, we continue to demonstrate that the same unbridgeable evolutionary chasms exist—further invalidating the myth of eukaryogenesis. https://answersingenesis.org/biology/microbiology/information-processing-differences-between-bacteria-and-eukarya/ Refutation of Symbiotic origin of Mitochondria - 2016 http://www.detectingdesign.com/Mitochondria_Evolution.html Shaking up cell biology - October 20, 2014 Excerpt: a team of scientists,,, has imaged mitochondria for the first time oscillating in a live animal,,, “The movements could last from tens of seconds to minutes, which was far longer and frequently at a faster tempo than observed previously in cell culture,” said Roberto Weigert, Ph.D.,,, The mitochondria also appear to synchronize their movements not only in an individual cell but, quite unexpectedly, into a linked network of oscillators vibrating throughout the tissue. “You look through the microscope, and it almost looks like a synchronized dance,” said Weigert. “The synchronization, to borrow an old cliché, tells us that we need to differentiate the forest from the trees — and vice versa — when studying mitochondria. It may be that the forest holds the key to understanding how mitochondria function in human health and disease.”,,, “We saw things in live animals that you don’t see in cell culture. The reasons, in this case, very well may be that the mitochondria continue to receive an influx of signals from the blood vessels, the nervous system, and their surrounding environment. The entire system can’t be reassembled (i)n cell culture.”,,, http://www.nih.gov/news/health/oct2014/nidcr-20.htm Mighty Mitochondria Conduct Energy Exquisitely - October 2011 Excerpt: The first three, called NADH dehydrogenase (Complex I), cytochrome c reductase, and cytochrome c oxidase, provide an “electron transport chain” that is used to pump protons into the space between the mitochondrion’s inner and outer membranes. The protons return through the inner membrane via the fifth machine, the turbine-like rotary motor ATP synthase (see CMI), which uses the proton motive force generated by the other machines to synthase ATP. Although cells can generate ATP without oxygen (anaerobic respiration), producing it through the mitochondrial machinery is much more efficient. On a busy day,,, approximately your body’s weight in ATP (is produced). http://crev.info/content/111007-mighty_mitochondria Powering the Cell: Mitochondria - video http://www.youtube.com/watch?v=RrS2uROUjK4
I don't know why the bacteria are so evil they wouldn't evolve in something else . Look at us ,we evolved from bacteria but now they wouldn't do the same thing anymore. Bacteria are shameless and against science. Didn't they hear of Darwin ? Sandy
Evolutionists always confuse imagination for science. Only imagination says eukaryotes evolved from populations of prokaryotes. ET
I always confuse mitochondria with midichlorians. Not that it matters under MRT as they're both imaginary Seversky
This reminds me of detective novels. In those stories the criminal always tries to commit the perfect crime, involving dozens of interlocking sequences of events that must work out precisely to avoid capture and evidence. Sherlock reconstructs the 147 steps of the sequence by deduction from axioms, and realizes that Step 78 failed to account for Uncle McTavish's unexpectedly late arrival. Aha! Gotcha! In real life criminals don't do any of this stuff. They just take things because they enjoy taking things, or kill because they enjoy killing. Same with cells and plants and animals. Living things live because they enjoy living. polistra
"Mitochondria were once free-living bacteria" this claim is a classic example of Darwian just-so-story... Like the whole Margulis-endosymbiosis just-so-story... Darwinian clowns can't never replicate these events (e.g. endosymbiosis) in their fancy labs... never... all what they have are just-so-stories martin_r

Leave a Reply