- Threose nucleic acid
Threose nucleic acid (TNA) is apolymer similar toDNA orRNA 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 andribose sugar backbone, respectively, whereas TNA's backbone is composed of repeatingthreose units linked byphosphodiester 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.
ee 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
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
year=2000
month=Nov
pmid = 11082060
doi=10.1126/science.290.5495.1347
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