Erice, Sicily

Date:
1971
Reference:
PP/CRI/E/1/19/8
Catalogue details

Licence: In copyright

Credit: Erice, Sicily. Source: Wellcome Collection.

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    cell. This process can be summarized as follows: viral RNA > RNA-DNA ) DNA-DNA ) DNA-DNA Some synthetic polymers are not only functional as template but also stimulate polymerization far better than neutral templates (about two orders of magnitude) ; i.e. dC-rG, in particular is very efficient. Other enzymatic activities have recently been shown in the virions; endonucleases, exonucleases, ligase, all of which would probably be involved in the integration process of the viral genome into the host genome. However, we are still ignorant of the number of different proteins which correspond to these various activities. The RNA-dependent.DNA-polymerase activity was first- discovered in RBA oncogenous viruses and was not found in normal cells? it was therefore suggested that the enzyme was specific to malignant cells. But it is too soon to say whether this mechanism has especially evolved in order to allow the genetic information of RNA tumor. viruses to be integrated into the genetic material, or- whether a system of that kind also exists in non infected .animal cells. An RNA - dependent DNA poly merase has been reported to exist in apparently normal human lymphocytes and a similar activity has also been shown in non oncogenous slow growing viruses. The problem of the relationship between this enzyme and carcinogenesis therefore still remains... However, the discovery of the enzyme is extremely interesting both from a theoretical and from a practical point of view. It can indeed be most fruitful to use it as a tool to synthesize-,...from a- messenger RNA, an information which, can become stable after integration into the DNA of the cell. References : Baltimore, Nature, 226 (1970) 1209. Temin, Mizutani, Nature, 226 (1970) 1211. Spiegelman, Burny, Das, Keydar, Schlom, Travicak, Watson, Nature, 22 7 (1970) 563. Spiegelman et al., Nature, 227 (1970) 1029. Spiegelman et al., Nature, 228 (1970) 430. Mizutani, Boettiger, Temin, Nature, 228 (1970) 424. Mizutani, Temin, Kodama, Wells, Nature Sew-Biology, 230 (1971) 232. Stone.,. Scolnick, Takernoto., Aaronson, Nature, 229 -(1971) 257. Parks, Todaro, Scolnick, Aaronson, Nature, 229 (1971) 258. Scolnick, Aaronson.., Todaro, ■ Parks, Nature, 229 (1971) 318. Duisberg, Helm, Canaani, Proc. Natl. Acad. Sci.., 68 (1971) 747.
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