Ribosome Study Challenges RNA World

Attention: open in a new window. PDFPrintE-mail

Ribosome study challenges RNA world according to reports in ScienceDaily and PLoS ONE 2012; 7 (3): e32776 DOI: 10.1371/journal.pone.0032776, 12 March 2012. Evolutionary biologists have long faced a “chicken and egg” problem of which biological molecules came first: proteins or nucleic acids (the NA in DNA and RNA). Both of these are highly complex molecules, and in living cells one cannot work without the other. In cells proteins are made by a complicated molecular machine named a ribosome, which consists of numerous proteins and RNA molecules. But RNA and DNA also require many proteins in their construction – hence the evolutionist’s dilemma when it comes to the origin of life: what came first, proteins or RNA.

In 1986 some biochemists proposed a theory that RNA molecules were the first to evolve and since then a hypothetical “RNA world” has been built up. Now Gustavo Caetano-Anollés, of University of Illinois, Urbana-Champaign and colleagues have made a close study of the proteins and RNA molecules in ribosomes and concluded the RNA world could not exist. According to Caetano-Anollésm “That world of nucleic acids could not have existed if not tethered to proteins”. The research team described the ribosome as a “ribonucleoprotein machine” and “you can't get RNA to perform the molecular function of protein synthesis that is necessary for the cell by itself”.

The researchers suggest ribosomes came about by RNA and proteins co-evolving from a less complex combination of RNA and proteins. Caetano-Anollés explained: “If the evolutionary build-up of ribosomal proteins and RNA and the interactions between them occurred gradually, step-by-step, the origin of the ribosome cannot be the product of an RNA world. Instead, it must be the product of a ribonucleoprotein world, an ancient world that resembles our own. It appears the basic building blocks of the machinery of the cell have always been the same from the beginning of life to the present: evolving and interacting proteins and RNA molecules”.

ScienceDaily

Editorial Comment: These researchers are correct in their conclusion that nucleic acids can only work in association with already existing proteins, and that is because nucleic acids and proteins are part of a self-replicating system, that can copy itself, but not make itself from a zero starting point. All of which points to a beginning as a fully functioning created system.

In the real world proteins are only useful when their component amino acids are put together in the correct sequence. There are many kinds of RNA and likewise these are only useful if their component molecules are put together in the correct sequence. The information for the correct sequence of both proteins and RNA is ultimately stored on DNA, which acts as an archive of information in the cell nucleus. However, that information cannot be put to use unless is it copied onto RNA – a process that requires many specific proteins. The question that has never been answered by biochemists who study proteins and nucleic acids is: Where did the information come from? It is probably not from the chemistry of the proteins, or the RNA or the DNA. Just as a computer disc contains information but doesn’t invent it, likewise these molecules contain information, but they don’t and can’t invent it. Information has been imposed on DNA by an outside Creator who used the properties of DNA to store information, and who used the properties of RNA and proteins to copy information and apply it.

Furthermore, DNA, RNA and proteins can only function in the controlled environment within a cell. They do not survive for long in the environment outside a protective cell membrane which means biochemists can store and use these molecules outside a cell only if they take stringent precautions to protect them from degrading, by providing an environment similar to that inside a cell. So how could such molecules function before the first cell came about?

The idea that proteins and nucleic acids evolved by chance random processes in some kind of molecular soup does not fit any known observations of how these molecules are made and how they function. All known observations however do fit the belief they were created to work together inside fully formed cells, along with the myriads of other molecules needed to keep living cells functioning, in an already created cell-friendly environment on a pre-designed life-friendly planet. (Ref. abiogenesis, biochemistry, organelles)

Evidence News 21 March 2012

q_and_a2
crc_youtube
outdoor_museum_panel
free_audio2