Threose nucleic acid
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2008-07-08T15:39:22Z
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Grammar
'''[[Threose]] nucleic acid''' (TNA) is a [[polymer]] similar to [[DNA]] or [[RNA]] but differing in the composition of its "backbone". TNA is not known to occur in existing life on Earth.
DNA and RNA have a [[deoxyribose]] and [[ribose]] sugar backbone, respectively, whereas TNA's backbone is composed of repeating [[threose]] units linked by [[phosphodiester bond]]s. The threose molecule is easier to assemble than ribose making it a possible precursor to RNA.
DNA-TNA hybrid chains have been made in the laboratory using DNA polymerase.
TNA can specifically base pair with RNA and DNA; this capability and chemical simplicity suggests that TNA could have preceded RNA as genetic material.
==See also==
*[[Abiogenesis]]
*[[Glycerol nucleic acid]]
*[[Peptide nucleic acid]]
==External links==
*[http://www.newscientist.com/article/mg17924052.500.html Was simple TNA the first nucleic acid on Earth to carry a genetic code?] - New scientist
*[http://www.sciencemag.org/cgi/content/summary/290/5495/1306 ORIGIN OF LIFE: A Simpler Nucleic Acid] - [[Leslie Orgel]]
==References==
* {{cite journal|
title=A Simpler Nucleic Acid|
last=Orgel|
first=Leslie|
journal=[[Science (journal)|Science]]|
year=2000|
month=Nov|
pages=1306–1307|
volume=290|
issue=5495|
doi=10.1126/science.290.5495.1306}}
* {{cite journal|
title=Modified nucleic acids on display|
last=Watt|
first=Gregory |
journal=Nature Chemical Biology|
year=2005|
month=Feb|
url=http://www.nature.com/nchembio/journal/vaop/nprelaunch/full/nchembio005.html|
doi = 10.1038/nchembio005}}
* {{cite journal|
title=Chemical etiology of nucleic acid structure: the alpha-threofuranosyl-(3'->2') oligonucleotide system.|
last=Schoning|
first=K|
coauthors=Scholz P; Guntha S; Wu X; Krishnamurthy R; Eschenmoser A|
journal=[[Science (journal)|Science]]|
year=2000|
month=Nov|
pmid = 11082060|
doi=10.1126/science.290.5495.1347
}}
{{Nucleic_acids}}
{{genetics-stub}}
[[Category:Nucleic acids]]
[[Category:polymers]]
[[it:Threose nucleic acid]]
[[pl:TNA]]
[[zh:蘇糖核酸]]