Polyribonucleotide binding

McDonald, J. R. and Agutter, P. S., The relationship between polyribonucleotide binding and the phosphorylation and dephosphorylation of nuclear envelope protein, FEBS Lett., 116[2], 145, 1980. 

A binding has also been observed with the RNA of virus [117] and bacteria [ 118 ] as well as in several synthetic polyribonucleotides [119, 120], giving rise to effects on physical properties. 

Bratcher SC, Sikka HC. 1982. Binding of 3,3 -dichlorobenzidine to DNA and polyribonucleotides in vitro. Chem Biol Interactions 38 369-375. 

In the previous chapters the reactivity of metal ions with the monomer units of nucleic acids has been discussed. This section will deal with the binding of transition metals to the polynucleotides. There are also three types of complexes to be expected the metal-ring, the intermediate and the metal chain complex. The effect of the ribose or deoxyribose residue on the stability constants can be neglected since the reactivity of these sugars with cations is extremely low. However, as it will be seen later, the hydrolysis of polyribonucleotides is markedly facilitated by interaction of metal ions with the 2 —OH groups of the ribose. 

Spectinomycin selectively inhibits protein synthesis in Gram-negative bacteria. The antibiotic binds to and acts on the 30S ribosomal subunit (see also Figure 75). Its action has similarities to that of the aminoglycosides however, spectinomycin is not bactericidal and does not cause misreading of polyribonucleotides. A high degree of bacterial resistance may develop as a result of mutation. 

Section 4.4.2 contains data on the strength and mode of binding of metal ions, and its effects on the conformation of DNA and synthetic polydeoxynucleotides, as well as polyribonucleotides. The properties of the synthetic polyribonucleotides are more easily presented along with those of polydeoxynucleotides than with those of single-chain mixed-sequence natural RNAs. 

This section contains information on how metals are bound to DNA, polydeoxynucleotides and polyribonucleotides. It consists of Table 2. Table 2. Binding characteristics. 

There is little information about the details of the translocation mechanism. A continuous polyribonucleotide chain is not essential, as translocation can occur with individual trinucleotides. It seems likely that movement of the mRNA is dependent on and tightly coupled to that of the tRNA with the binding sites for the tRNA providing the precision for movement by exactly one codon. Presumably, binding of EF-G and GTP after release of EF-Tu-GDP following peptide bond synthesis induces a conformational change in the ribosome which leads to translocation. 

Upon the formation of an open-promoter complex, polyribonucleotide chain formation may commence. RNA polymerase contains two nucleotide-binding sites called the initiation and the elon-... 

Steinberg et al. (1969) have shown the existence of antibodies binding specifically with poly rl-poly rC labelled with in the sera of NZB and NZB/W mice as well as in the sera of SLE patients. This reaction can be inhibited by double-helical polyribonucleotide complexes. They showed also that these antibodies are different from anti-native DNA antibodies because the latter are not inhibited by double-helical polyribonucleotides. They later confirmed these results (Talal et al., 197I) by studies of reciprocal inhibition... 

Free DDA concentration (x10 ) M Figure 10.2 Binding isotherms of DDA with native (1) and denatured (2) DNA, with single-stranded polyribonucleotides poly (U) (3), poly(A) (5), as well as with double helix poly(U) poly(A) (4). (From Ref. [10].)... 

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