August 6, 2004 | David F. Coppedge

Cell Nucleus Complexity Baffles Evolutionists

In her inimitable way, Science reporter Elizabeth Pennisi has once again portrayed a scientific controversy undergoing active ferment.  This time it’s about the evolutionary origin of cell nuclei, which she terms “specialized, DNA-filled command centers.”1  At the conclusion, she gives prominence to a “provocative, but circumstantial and controversial” suggestion that viruses taught cells how to wrap their DNA in double membranes with controlled access.  Since the idea presupposes that viruses preceded all three domains of life – prokarya, eukarya and archaea – “If this is true, then we are all basically descended from viruses,” as a believer puts it.  The idea is unpalatable to some.  “I do not believe [it],” a German molecular biologist retorts.  “The idea of the viruses ‘inventing’ [eukaryotic cells] from scratch is hard for me to conceive.”
    Pennisi treats the new viral theory as tentative at best.  What’s more revealing in her article are the problems with previously-popular ideas, and why.  According to her, the key insight at a meeting in France last month on the subject was: “They had underestimated the complexity of the eukaryotic cell’s 1.5-billion-year-old precursor.  The data presented indicated that this ancestral cell had more genes, more structures, and more diverse biochemical processes than previously imagined.”  For a glimpse why, look at Pennisi’s brief description of the nucleus:

Each nucleus in a eukaryotic cell consists of a double lipid-based membrane punctuated by thousands of sophisticated protein complexes called nuclear pores, which control molecular traffic in and out of the organelle.  Inside, polymerases and other specialized enzymes transfer DNA’s protein-coding message to RNA.  Other proteins modify the strands of RNA to ensure that they bring an accurate message to the ribosomes outside the nucleus.  The nucleus also contains a nucleolus, a tightly packed jumble of RNA and proteins that are modified and shipped out of the nucleus to build ribosomes.
(For more on the nuclear pore complex, see 06/17/2002 and 01/18/2002 headlines.)

Eukaryotes are distinguished from bacteria by their double-membrane nuclei.  “The nuclear distinction between prokaryotes and eukaryotes shaped early speculation about the development of complex life,” Pennisi says about ideas floating around up to the 1970s.  Some thought eukaryotes were evolved prokaryotes, and others thought prokaryotes were degenerate eukaryotes.  But then Carl Woese created new woes by identifying bacteria-like cells that were distinct from both prokaryotes and eukaryotes: so different, in fact, to warrant classification in their own domain – archaea.  Others soon were surprised to find that eukaryotes appeared to have genes from both bacteria and archaea.
    So another story was born, the endosymbiont or merger hypothesis.  This proposed that eukaryotes arose from “the ancient symbiotic partnership between bacteria and archaea.”  That theory came under fire from the discovery of faint but distinct nuclei in an unusual group of bacteria, named planctomycetes, that live in soil and fresh water.  Some of these planctomycetes have organelles and double-membraned sacs of DNA and RNA.  According to a critic of the merger model, these observations “turn the dogma that ‘prokaryotes have no internal membranes’ upside down”  Now, it seems no one is sure which way is up.
    There’s more to cause vertigo for evolutionists: the complexity of the nuclear pore complexes (NPCs).  “Explaining these structures has always posed a sticking point for nuclear evolution.”  For one thing, “without pores, the nucleus can’t function.”  But for another thing, Pennisi continues, the same planctomycetes, and possibly some other archaea and prokaryotes, apparently possess structures resembling these complex traffic-control gates.  “Bacteria with nuclear pores and internal membranes, features typically considered eukaryote-specific, suggest that the nucleus was born much earlier than traditionally thought.”
    For some, that leaves as the leading contender the controversial theory that viruses first invented the nucleus.  This, however, only pushes the complexity of nuclei and their pores farther back in time, and foists a huge design problem on earth’s most primitive biological entities.  That is why the molecular biologist quoted earlier can’t believe that simple viruses created such complex structures from scratch.  Pennisi shares a few speculations, based on circumstantial evidence, how it might have happened.  But when she ends by pushing the answer to the future, it underscores the fact that no current theory accounts for the origin of the nucleus:

Did a virus provide the first nucleus?  Or was it something an early bacterial cell evolved, either on its own or in partnership with an archaeum?  To resolve the origin of the nucleus, evolutionary biologists are exploring new techniques that enable them to determine relationships of microorganisms that go much further back in time….

The biologists in France argued and discussed many ideas.  “But when it came to accounting for how the nucleus was born,” Pennisi admits, “no single hypothesis bubbled to the top.”  She quotes French molecular biologist Patrick Forterre who said, “It’s like a puzzle.  People try to put all the pieces together, but we don’t know who is right or if there is still some crucial piece of information missing.”

1Elizabeth Pennisi, “Evolutionary Biology: The Birth of the Nucleus,” Science, Vol 305, Issue 5685, 766-768, 6 August 2004, [DOI: 10.1126/science.305.5685.766].

The crucial piece of missing information is information itself.  Information: DNA, logic, codes, controlled access, complex systems of integrated parts: these are all indicators of intelligent design.  This would be obvious if the biologists at that meeting would only think outside the Darwinian box in which they have imprisoned themselves.  Look at what contortions they have to go through to account for such biological complexity by chance.  As usual, the answer is somewhere out there in the future.  Also as usual, the same trend is seen here as in everything else in biology, and even in paleontology and cosmology: more complexity, further back toward the beginning.
    Poor Elizabeth.  She has reported on so many of these evolutionist hand-wringing sessions you would think she might have taken up gardening by now to maintain her sanity.  But that might not help.  Just looking at the soil and thinking about those planctomycetes, and looking at the leaves and thinking about those nuclear pore complexes, DNA decoders accurately translating messages into specialized enzymes, all those shipping and receiving docks, and all the other thousands of sophisticated complexes working together in those command centers called nuclei might bring the stress and anxiety right back again.  “Come unto Me,” said the Designer, “all you who are weary and heavy laden, and I will give you rest.”

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