Complementary base-pairs

In principle, the Maxam-Gilbert method can provide the total sequence of a dsDNA molecule just by determining the purine positions on one strand and then the purines on the complementary strand. Complementary base-pairing rules then reveal the pyrimidines along each strand, T complementary to where A is, C complementary to where G occurs. (The analogous approach of locating the pyrimidines on each strand would also provide sufficient information to write the total sequence.)... 

Perahia, D., and A. Pullman. 1978. The Molecular Electrostatic Potentials of the Complementary Base Pairs of DNA. Theor. Chim. Acta 48, 263. 

Flanking sequences which dock ribozyme at the appropriate sequence of the appropriate mRNA via complementary base pairing... 

Table 7 Association and dissociation rate constants for the binding of 22 to d(GCG-Y-GCG) complementary base paired oligonucleotides at 25 °C...

Stem the beacon stem sequence lies on both the ends of the loop. It is a few complementary base pairs long. 

To say that RNA molecules are single-stranded molecules is not the same as saying that they have no higher-order structures, hi fact they have several. The formation of Watson-Crick complementary base pairs is a driving force for formation of higher-order structures. These include the stem-loop and hairpin secondary structures, as well as more complex tertiary structures. Of particular note, are the complex structures for transfer RNAs, tRNAs. Examples are provided in figure 12.5 (note that there are several nnnsnal bases in these structnres this is typical of tRNAs but not of RNA molecnles in general). These strnctures are intimately related to the function of these molecnles as adaptors in the process of protein synthesis, as developed in the next chapter. 

Some ion-radical mechanisms are implicated in the DNA damage others can be described as repairing the damage. In normal DNA, bases belonging to the two opposite strands are bound by relatively weak hydrogen bonds. In case of complementary base pairs, several hydrogen bonds are formed they are depicted in Scheme 3.71. 

Another important application of cDNAs is to identify specific proteins in a tissue homogenate or tissue section. Since cDNAs undergo complementary base pairing, adding a radioactively labelled cDNA to a homogenate or tissue slice will bind it to the complementary sequence by a process of hybridization. Thus the amount of radioactive cDNA that hybridizes to the tissue or tissue extract is a measure of the amount of mRNA that is complementary to it. When this procedure is undertaken on slices of brain, it is known as in situ hybridization. In this way it is possible to determine the distribution of specific receptors in a tissue by accurately determining the distribution of mRNA that encodes for the receptor protein. This is a particularly valuable technique for the administration of psychotropic drugs. 

Forward and Reverse Work Distributions Cross at W = AG. In order to obtain AG we can measure the forward and reverse work distributions, Pp(W) and Pr(—W), and look at the work value W where they cross, P-p W ) =Rr(—W ). According to Eq. (41), both distributions should cross at W = AG independently of how far the system is driven out of equilibrium (i.e., independently of the pulling speed). Figure 9 shows experiments on a short canonical RNA hairpin CD4 (i.e., just containing Watson-Crick complementary base pairs) at three different pulling speeds, which agree very well with the FT prediction. 

For a given gene, the corresponding mRNA is complementary to (matches the base pairing of) the strand of the DNA where the information in the gene is stored. The conventions on nucleic acid nomenclature, nucleic acid structure, and the Wat-son-Crick rules for complementary base-pairing are given in Chapter 3. 

Putting together much published data, Watson and Crick postulated that native DNA consists of two antiparallel chains in a right-handed double-helical arrangement. Complementary base pairs, A=T and G C, are formed by hydrogen bonding within the helix. The base... 

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