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The [[RNA|RNA]] world hypothesis is one possible explaination to the paradox surrounding the origin of life on Earth. It was proposed by [[Francis_Crick|Francis Crick]] and his team in the late 1960s <ref>Akst J. (2014) RNA World 2.0. The Scientist magazine. Available from: http://www.the-scientist.com/?articles.view/articleNo/39252/title/RNA-World-2-0/ [last accessed: 28.11.2014]</ref>. The central dogma of molecular biology states that [[DNA|DNA]] is required to produce proteins, with RNA<span style="line-height: 1.5em">&nbsp;</span><span style="line-height: 1.5em">acting as an intermeidate&nbsp;<ref>Londish, H., Berk, A., Kaiser, C.A., Krieger, M., Bretscher, A., Ploegh, H., Amon, A. &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp; Scott, M.P. (2013) Molecular Cell Biology. 7th edn. Basingstoke: Macmillan Higher Education. p. 116.</ref>. The paradox arises due to the fact that DNA is required to produce proteins, but protiens are required to produce DNA&nbsp;<ref>Alberts, B., Bray, D., Hopkins, K., Johnson, A., Lewis, J., Raff, M., Roberts, K. and Walter, P. (2014) Essential Cell Biology. 4th edn. Abingdon: Garland Science. p. 253.</ref>. This raises the question how did such a interdependant system first arise?</span>  
The [[RNA|RNA]] world hypothesis is one possible explaination to the paradox surrounding the origin of life on Earth. It was proposed by [[Francis_Crick|Francis Crick]] and his team in the late 1960s <ref>Akst J. (2014) RNA World 2.0. The Scientist magazine. Available from: http://www.the-scientist.com/?articles.view/articleNo/39252/title/RNA-World-2-0/ [last accessed: 28.11.2014]</ref>. The central dogma of molecular biology states that [[DNA|DNA]] is required to produce proteins, with RNA<span style="line-height: 1.5em">&nbsp;</span><span style="line-height: 1.5em">acting as an intermeidate&nbsp;<ref>Londish, H., Berk, A., Kaiser, C.A., Krieger, M., Bretscher, A., Ploegh, H., Amon, A. &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp; Scott, M.P. (2013) Molecular Cell Biology. 7th edn. Basingstoke: Macmillan Higher Education. p. 116.</ref>. The paradox arises due to the fact that DNA is required to produce proteins, but protiens are required to produce DNA&nbsp;<ref>Alberts, B., Bray, D., Hopkins, K., Johnson, A., Lewis, J., Raff, M., Roberts, K. and Walter, P. (2014) Essential Cell Biology. 4th edn. Abingdon: Garland Science. p. 253.</ref>. This raises the question how did such a interdependant system first arise?</span>  


The RNA world hypothesis states that due to the ability of RNA to both store genetic information and catalyse chemical reactions, it may be the precursor to current life&nbsp;<ref>Alberts, B., Johnson, A., Lewis, J., Raff, M., Roberts, K. and Walter, P. (2008) Molecular Biology of the Cell. 5th edn. Abingdon: Garland Science. pp. 400-408.</ref>. &nbsp;However the sequence of reactions which leads to the spontaneous synthesis of [[RNA|RNA]] in the prebiotic environment has not been scientificaly revealed&nbsp;<ref>Akst J. (2014) RNA World 2.0. The Scientist Magazine. Available from: http://www.the-scientist.com/?articles.view/articleNo/39252/title/RNA-World-2-0/ [last accessed: 28.11.2014]</ref>, therefore the hypothesis has failed to gain general scientific consensus.<br>
The RNA world hypothesis states that due to the ability of RNA to both store genetic information and catalyse chemical reactions, it may be the precursor to current life&nbsp;<ref>Alberts, B., Johnson, A., Lewis, J., Raff, M., Roberts, K. and Walter, P. (2008) Molecular Biology of the Cell. 5th edn. Abingdon: Garland Science. pp. 400-408.</ref>. &nbsp; Experiments have supported this theory by showing that Rrandomly generated RNA sequences can have useful funtctions such as an experiment caried out in the 1950s at the Whitehead Institute of Biomedical Research who reported on "Structurally Complex and Highly Active RNA Ligases Derived from Random RNA Sequences". <ref> Eric H. Eckland, Jack W. Szostak and David P. Bartel, "Structurally Complex and Highly Active RNA Ligases Derived from Random RNA Sequences" [abstract], doi:10.1126/science.7618102, p 364-370 v 269, Science, 21 July 1995. </ref> Other experiments have also shown RNAs with the ability to self-replicate <ref> Johnston, W. K.; Unrau, P. J.; Lawrence, M. S.; Glasner, M. E.; Bartel, D. P. (2001). "RNA-Catalyzed RNA Polymerization: Accurate and General RNA-Templated Primer Extension". Science 292 (5520): 1319–25. doi:10.1126/science.1060786. PMID 11358999. </ref> and Self-catalyse <ref> Huang, Yang, and Yarus, RNA enzymes with two small-molecule substrates. Chemistry & Biology, Vol 5, 669-678, November 1998 </ref> as well as the ability to perform aminoacid ligation <ref> Erives A (2011). "A Model of Proto-Anti-Codon RNA Enzymes Requiring L-Amino Acid Homochirality". J Molecular Evolution 73 (1–2): 10–22. doi:10.1007/s00239-011-9453-4. PMC 3223571. PMID 21779963. </ref> and peptide bond formation. <ref> Atkins, John F.; Gesteland, Raymond F.; Cech, Thomas (2006). The RNA world: the nature of modern RNA suggests a prebiotic RNA world. Plainview, N.Y: Cold Spring Harbor Laboratory Press. ISBN 0-87969-739-3. </ref> Despite this, the sequence of reactions which leads to the spontaneous synthesis of [[RNA|RNA]] in the prebiotic environment has not been scientificaly revealed&nbsp;<ref>Akst J. (2014) RNA World 2.0. The Scientist Magazine. Available from: http://www.the-scientist.com/?articles.view/articleNo/39252/title/RNA-World-2-0/ [last accessed: 28.11.2014]</ref>, therefore the hypothesis has failed to gain general scientific consensus.<br>


=== References  ===
=== References  ===

Revision as of 14:26, 22 October 2015

The RNA world hypothesis is one possible explaination to the paradox surrounding the origin of life on Earth. It was proposed by Francis Crick and his team in the late 1960s [1]. The central dogma of molecular biology states that DNA is required to produce proteins, with RNA acting as an intermeidate [2]. The paradox arises due to the fact that DNA is required to produce proteins, but protiens are required to produce DNA [3]. This raises the question how did such a interdependant system first arise?

The RNA world hypothesis states that due to the ability of RNA to both store genetic information and catalyse chemical reactions, it may be the precursor to current life [4].   Experiments have supported this theory by showing that Rrandomly generated RNA sequences can have useful funtctions such as an experiment caried out in the 1950s at the Whitehead Institute of Biomedical Research who reported on "Structurally Complex and Highly Active RNA Ligases Derived from Random RNA Sequences". [5] Other experiments have also shown RNAs with the ability to self-replicate [6] and Self-catalyse [7] as well as the ability to perform aminoacid ligation [8] and peptide bond formation. [9] Despite this, the sequence of reactions which leads to the spontaneous synthesis of RNA in the prebiotic environment has not been scientificaly revealed [10], therefore the hypothesis has failed to gain general scientific consensus.

References

  1. ↑ Akst J. (2014) RNA World 2.0. The Scientist magazine. Available from: http://www.the-scientist.com/?articles.view/articleNo/39252/title/RNA-World-2-0/ [last accessed: 28.11.2014]
  2. ↑ Londish, H., Berk, A., Kaiser, C.A., Krieger, M., Bretscher, A., Ploegh, H., Amon, A. &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp; Scott, M.P. (2013) Molecular Cell Biology. 7th edn. Basingstoke: Macmillan Higher Education. p. 116.
  3. ↑ Alberts, B., Bray, D., Hopkins, K., Johnson, A., Lewis, J., Raff, M., Roberts, K. and Walter, P. (2014) Essential Cell Biology. 4th edn. Abingdon: Garland Science. p. 253.
  4. ↑ Alberts, B., Johnson, A., Lewis, J., Raff, M., Roberts, K. and Walter, P. (2008) Molecular Biology of the Cell. 5th edn. Abingdon: Garland Science. pp. 400-408.
  5. ↑ Eric H. Eckland, Jack W. Szostak and David P. Bartel, "Structurally Complex and Highly Active RNA Ligases Derived from Random RNA Sequences" [abstract], doi:10.1126/science.7618102, p 364-370 v 269, Science, 21 July 1995.
  6. ↑ Johnston, W. K.; Unrau, P. J.; Lawrence, M. S.; Glasner, M. E.; Bartel, D. P. (2001). "RNA-Catalyzed RNA Polymerization: Accurate and General RNA-Templated Primer Extension". Science 292 (5520): 1319–25. doi:10.1126/science.1060786. PMID 11358999.
  7. ↑ Huang, Yang, and Yarus, RNA enzymes with two small-molecule substrates. Chemistry & Biology, Vol 5, 669-678, November 1998
  8. ↑ Erives A (2011). "A Model of Proto-Anti-Codon RNA Enzymes Requiring L-Amino Acid Homochirality". J Molecular Evolution 73 (1–2): 10–22. doi:10.1007/s00239-011-9453-4. PMC 3223571. PMID 21779963.
  9. ↑ Atkins, John F.; Gesteland, Raymond F.; Cech, Thomas (2006). The RNA world: the nature of modern RNA suggests a prebiotic RNA world. Plainview, N.Y: Cold Spring Harbor Laboratory Press. ISBN 0-87969-739-3.
  10. ↑ Akst J. (2014) RNA World 2.0. The Scientist Magazine. Available from: http://www.the-scientist.com/?articles.view/articleNo/39252/title/RNA-World-2-0/ [last accessed: 28.11.2014]


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