DNA and RNA Strands

SCHEME 6.5 Modular fragments made from H3PO4 by unclicking O—H bonds. The electrons available to participate in connectivity after unclicking are highlighted in red. 

SCHEME 6.6 (a) The nucleotides of DNA and RNA drawn in the implicit manner. The circled group P is a phosphate, drawn explicitly on the right-hand side. The circled group B is a base, (b) The four DNA bases are A, C, G, and T, while, in RNA, the T is replaced by U. The red lines indicate the sites of connection of these bases to the sugar fragment. 

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The last section of this chapter includes in brief a procedure of McF adden (9) for in situ hybridization. In situ hybridization relies on the complementarity of the bases contained within DNA and RNA. In addition to the hybridization (reassociation) of complementary DNA strands, hybridization is possible between DNA and RNA strands that are complementary. Also, hybridization is possible between a synthetic sequence and a sequence of biological origin. In situ hybridization may be used to determine the location of a specific nucleic acid sequence within a cell. The procedure requires the use of a probe for the sequence of interest. The probe, in turn, must be complementary to the sequence of interest. The probe may be either single stranded or double stranded, DNA or RNA. There must exist a method by which to detect the probe. 

Sequence-specific pairing of DNA and RNA strands is essential for the storage, transmission, and expression of genetic information, which forms the basis for techniques such as polymerase chain reaction, hybridization techniques, and DNA chip arrays. Having demonstrated the sequence-independent namre in the stabilities of... 

Mechanism of Action An alkylating agent that inhibits DNAand RNA protein synthesis by cross-linking with DNA and RNA strands, preventing cell growth. Cell cycle-phase nonspedflc. Therapeutic Effect Potent immunosuppressant. Pharmacokinetics Well absorbed from the G1 tract. Protein binding low. Crosses the blood-brain barrier. Metabolized in the liver to active metabolites. Primarily excreted in urine. Removed by hemodialysis. Half-life 3-12 hr. 

For the sake of clarity, we are being somewhat cavalier about directions on the DNA and RNA strands. Please consult a biochemistry text if you wish to explore this topic in greater depth. 

Peptide nucleic acids, (I), that are not polynucleotides will form complementary DNA and RNA strands stronger than the corresponding DNA, as reported... 

Table XXII-2 is a catalog of the genes, nucleotides (DNA and RNA strands), enzymes, and a few major proteins identified to date in tobacco. The format of this table differs from those in most other chapters since only one of the tobacco constituents is transferred intact to MSS (phytuberin). As a result, the Tobacco Smoke column was deleted from Table...

CD and absorption spectra of four duplexes with different mixtures of complementary DNA and RNA strands, each duplex containing alternating A T and G C base pairs (except that T in the DNA strands is replaced by U in the analogous RNA strands). The RNA duplex r(AG)i2 r(CU),2 had a negative band at 210 nm and a larger positive band above 250 nm than did the DNA duplex d(AG),2-d(CT) 2. These CD features are characteristics that generally distinguish the A-RNA conformation from the B-DNA conformation. ... 

The methods described previously can be used to build a polynucleoside. In actual practice, special protecting groups and a relatively standard set of reaction conditions are required. When completed, however, the protecting groups are removed and the nucleic acid unit is cleaved from the polymer. This sequence can be automated and machines can prepare DNA and RNA strands if the reagents for coupling, as well as protection and deprotection reagents, are supplied and, of course, there is a supply of each individual nucleotide. 

There are five nucleobases that make up DNA and RNA strands adenine (A), guanine (G), cytosine (C), thymine (T), and uracil (U), the structures of which are shown in Figure 1. These bases are categorized as either purines (two... 

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