Properties of RNA in formamide

Abstract

ture of low thermal stability appeared, which, it was suggested, might be unrelated to that present in the native state in water. There is less certainty about two-stranded, fully base-paired RNA, which is reported to be incompletely melted in formamide at room temperature (Strauss et al., 1968). We have examined the conformation and other relevant properties of RNA and its constituents in formamide under the conditions used in electrophoretic experiments. The results are described below, as also is evidence for a strong preferential interaction of RNA with water. Materials and MethodsEscherichia coli rRNA was prepared from packed MRE 600 cells by the method of Robinson and Wade (1968). Rabbit reticulocyte rRNA was extracted by the phenolsodium dodecyl sulfate method from purified ribosomes BIOCHEMISTRY, VOL.

Phytohormone control of translatable RNA populations in sexual organogenesis of the dioecious plant Mercurialis annua L. (2n = 16)

“…We therefore used 2-10% sucrose gradients with formamide (denaturing conditions) which is known to break the non-covalent bonds between RNA chains (20,34,38). Any possible aggregates are dissociated for all formamide concentrations equal or greater than 50% and any cryptic breaks which could have been induced would then become apparent and show up as a decrease in the sedimentation constant.…”

Structure of viroid replicative intermediates: physico-chemical studies on SP6 transcripts of cloned oligomeric potato spindle tuber viroid

“…Suprapure NaCl (Merck) was used in thermal denaturation buffers. Formamide was purified according to the procedure of Pinder et al (15). SP6 transcripts of PSTV As described earlier (14), synthetic PSTV replication intermediates were made by inserting one to six PSTV DNA copies (connected 'head-to-tail') into plasmid pSP62-PL downstream of the promoter for SP6 RNA polymerase.…”

Phylogenetic Relationships Between Mycoplasmas and Other Procaryotes Based upon the Electrophoretic Behavior of Their Ribosomal Ribonucleic Acids

“…Formamide gels were prepared by the method of Pinder et al. (17) with the following modifications: 99% formamide (Matheson, Coleman, Bell) was deionized with mixed-bed ion-exchange resin (Bio-Rad Amberlite MB-11, filtered, and then buffered with 0.02 M diethylbarbituric acid (barbital). The pH was adjusted to 9.0 with 1 N hydrochloric acid or 1 N sodium hydroxide.…”

“…Under these conditions, where the secondary and tertiary structure of the rRNA is destroyed, the RNAs can all be assumed to be configurational homologs (17). Therefore, migration of molecules in gels that are configurational homologs is inversely proportional to the logarithm (10,17).…”