Researchers from Tohoku University have discovered the evidence that borate selectively stabilize ribose from among its stereoisomers, aldopentoses. The stabilization may have played a key role for the prebiotic selection of RNA components and for the formation of RNA. The work was published online on Decembers 24 in Origins of Life and Evolution of Biospheres.
Life based on RNA is considered to have predated current life based on DNA and protein. For the construction of the RNA-based life (RNA world), natural processes on the prebiotic world must have selected the RNA components and led to their accumulation.
Ribose, an aldopentose, is the least stable component the building brock of RNA: ribose, nucleic acid bases, and phosphoric acid. Ribose is also less stable compared with its stereo isomeric aldopentoses. These facts have been significant weaknesses of the RNA world hypothesis.
The lead author, Yoshihiro Furukawa, assistant professor of geochemistry in the Department of Earth Science at Tohoku University, developed advanced chromatographic techniques to quantify each aldopentoses including ribose with Mana Horiuchi, Shimadzu Corporation (former graduate student of Tohoku University) and then, measured the stabilities of aldopentoses with the techniques. Dr. Furukawa and Dr. Takeshi Kakegawa, professor of geochemistry in the Department Earth Science at Tohoku University constructed the application of the experimental results to prebiotic world and concluded that borate helped the selection of the RNA sugar (ribose) in prebiotic seafloor where high borate concentrations might have been expected. The results provide new evidence to compensate the weakness of the RNA world.
This research was supported by JSPS KAKENHI (Grant Number: 22654063, 24244084, and 23740402) and a Tohoku University Global COE program "Global Education and Research Center for Earth and Planetary Dynamics".
Department of Earth Science, Tohoku University
e-mail: furukawa*m.tohoku.ac.jp(Replace * with @)
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