Re-creating an RNA world

  title={Re-creating an RNA world},
  author={Ulrich F. M{\"u}ller},
  journal={Cellular and Molecular Life Sciences CMLS},
  • U. F. Müller
  • Published 2 May 2006
  • Biology
  • Cellular and Molecular Life Sciences CMLS
Abstract.The RNA world hypothesis states that life originated via a system based on RNA genomes and RNA catalysts. Researchers have been trying to develop such a system since catalytic RNAs (ribozymes) were discovered in 1982. This review summarizes the recent progress made in that endeavor and outlines the obstacles that remain to be overcome. After giving a short background on prebiotic chemistry and in vitro evolution, the discussion focuses on the generation of three important components of… 

Question 5: On the Chemical Reality of the RNA World

Concerning the achievement of high local RNA molecules concentration and the aetiology of unique sequence under plausible prebiotic conditions, concerns with regard to the chemical constrains that such scenario should have met to be feasible are addressed.

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An RNA-capping ribozyme is isolated and characterized that retains stereochemistry during the synthesis of a 5'-5' RNA cap, and oligonucleotides are found that are able to form transient unimolccular loop structures closed by 3s little as one base-pair to be viable substrates.

Reviving the RNA World: An Insight into the Appearance of RNA Methyltransferases

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Lower temperature optimum of a smaller, fragmented triphosphorylation ribozyme.

A 96-nucleotide long ribozyme is developed, which generates a chemically activated 5'-phosphate (a 5'-triph phosphate) from a prebiotically plausible molecule, trimetaphosphate, and an RNA 5'-hydroxyl group by fragmenting the ribo enzyme into multiple RNA strands, and by successively removing its longest double strand.

RNA self-processing towards changed topology and sequence oligomerization

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Trans Hammerhead Ribozyme: Ligation vs. Cleavage

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Nonenzymatic Recombination of RNA: Possible Mechanism for the Formation of Novel Sequences

It is suggested that similar reactions could contribute to the development of the ‘RNA world’, but could also proceed in vivo within variously structured RNA or RNA complexes containing loops, bulges, or dangling ends, providing an emergence of novel RNA sequences.

Catalytic DNA (deoxyribozymes) for synthetic applications-current abilities and future prospects.

Broadly defined, deoxyribozymes may have the greatest potential for catalyzing reactions in which the high selectivities of 'enzymes' are advantageous relative to traditional small-molecule catalysts.

Ancient Retrotransposons as Possible Remnants of the Primitive RNPWorld

RNA chaperoning provided by basic peptides within highly crowded RNA populations may actively create novel information essential for the basic mechanisms of life.



5 Re-creating an RNA Replicase

The idea that certain RNA sequences can use the information from one RNA strand to accurately and efficiently produce another RNA is central to the RNA World hypothesis and relies on some radical assumptions regarding the intrinsic catalytic capability of RNA.

Prebiotic chemistry and the origin of the RNA world.

  • L. Orgel
  • Biology
    Critical reviews in biochemistry and molecular biology
  • 2004
The demonstration that ribosomal peptide synthesis is a ribozyme-catalyzed reaction makes it almost certain that there was once an RNA World, and a discussion of genetic systems simpler than RNA that might have "invented" RNA is discussed.

Processivity of ribozyme-catalyzed RNA polymerization.

A method of measuring polymerase processivity that is particularly useful in the case of an inefficient polymerase is developed, allowing it to be demonstrated that the polymerase ribozyme, despite its inefficiency, is partially processive.

A multisubunit ribozyme that is a catalyst of and template for complementary strand RNA synthesis.

Results suggest that prebiotically synthesized oligonucleotides might have been able to assemble into a complex capable of self-replication.

1 Prospects for Understanding the Origin of the RNA World

The existence of an RNA world as a precursor of the authors' DNA/protein world is a hypothesis and three basic assumptions are included: At some time in the evolution of life, genetic continuity was assured by the replication of RNA; Watson-Crick base-pairing was the key to replication; and genetically encoded proteins were not involved as catalysts.

Ribozyme catalysis: not different, just worse

Results from structural and biochemical studies show that natural ribozymes use an impressive range of catalytic mechanisms, beyond metalloenzyme chemistry and analogous to more chemically diverse protein enzymes.

Continuous in vitro evolution of catalytic function.

Both the catalytic rate and amplification rate of the RNAs improved substantially as a consequence of mutations that accumulated during the evolution process.

Nucleic acid enzymes: playing with a fuller deck.

  • G. F. Joyce
  • Biology, Chemistry
    Proceedings of the National Academy of Sciences of the United States of America
  • 1998
The repertoire of chemical reactions that can be catalyzed by RNA is broad and expanding steadily, and the number of novel RNA enzymes developed through in vitro evolution is expanding steadily.

RNA, the first macromolecular catalyst: the ribosome is a ribozyme.