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I get conflicting answers. One would think if it was true, it would be rather seminal and widely known.

There are papers from Khorana[1], Holland[2], and Bretscher[3] (late 60s) that suggest that it is quite easy in the presence of antibiotics like neomycin.

But more recent papers like this one[4] still openly ask the question, and that the only thing we know is that the initial ribosome binding step is similar between RNA and DNA.

I can't reconcile these papers.

  1. Morgan AR, Wells RD, Khorana HG. 1967. Studies on polynucleotides. LXXIV. Direct translation in vitro of single-stranded DNA-like polymers with repeating nucleotide sequences in the presence of neomycin B. Journal of Molecular Biology, 26(3):477-497, doi:1016.10/0022-2836(67)90316-6.
  2. McCarthy BJ, Holland JJ. 1965. Denatured DNA as a direct template for in vitro protein synthesis. Proceedings of the National Academy of Sciences USA, 54(3):880-886.
  3. Bretscher MS. 1969. Ribosome Initiation and the Mode of Action of Neomycin in the Direct Translation of Single-Stranded fd DNA. Cold Spring Harbor Symposia on Quantitative Biology, 34:653-651, doi:10.1101/SQB.1969.034.01.075.
  4. Damiana L, Marty-Detravesa C, Winterhalterc M, Fourniera D, Paquereaua L. 2009. Single-strand DNA translation initiation step analyzed by Isothermal Titration Calorimetry. Biochemical and Biophysical Research Communications, 385(3): 296-301, doi:10.1016/j.bbrc.2009.05.044.
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  • $\begingroup$ But the first sentence of the abstract of the 2009 paper says that it is (still) an open question and refers to discrepancies: Is single-strand DNA translatable? Since the 60s, the question still remains whether or not DNA could be directly translated into protein. Some discrepancies in the results were reported about functional translation of single-strand DNA but all results converged on a similar behavior of RNA and ssDNA in the initiation step. This paper looked only at initiation and binding, no protein product was detected AFAICT. I think this is what they are referring to in terms of ef $\endgroup$
    – user1457
    Sep 26, 2012 at 14:48

1 Answer 1

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As far as I can tell from the paper you linked to (Damiana et al) it is possible but inefficient:

Naturally, we tried to translate ssDNA, but as previously described elsewhere, direct DNA translation was not really efficient in absence of antibiotics such as neomycin [5] and [6]. It seemed that the elongation phase was the limiting step in the direct translation of single-stranded DNA. Whether direct participation of DNA in protein synthesis could play any role in vivo must be excluded, although such a role could be attractive for modelling the evolution of the earliest forms of life.

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  • $\begingroup$ Yet Damiana et al. still say: "Is single-strand DNA translatable?" "With these experiments, our purpose was not to test whether or not ssDNA could be used as a translational template in cells but..." By "not really efficient", they mean they could not detect their intended peptide product, which seems more like "no, it doesn't work". "All previous work had tested if ssDNA allowed direct translation, but results obtained were not really convincing and the possibility that only some steps could be restrictive was not checked." $\endgroup$
    – mdna
    Oct 2, 2012 at 16:50

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