Hexanucleotides, random

Denature 1 pg of probe DNA (single stranded) with 5 pg of random hexanucleotide primers by boiling for 5 minutes and then rapidly chill on ice. Incubate at least 10 minutes to allow the primers to hybridize to random sites within the probe DNA. 

Biotinylated dUTP can also be used to label DNA probes by a different method, namely random-primed labeling (4). The principle of this method is based on the reannealing of hexadeoxyribonucleotide primers, which have random specificity, to the denatured DNA strands. The DNA to be labeled has to be linearized and denatured before the strands are used as templates in the labeling reaction. The complementary strands are synthesized from the 3 OH termini of the reannealed hexanucleotides by the Klenow fragment of E. coli DNA polymerase I. The primers reanneal at random sites of the template strands, so that the synthesis of the complementary strands is primed at random sites. If one of the deoxyribonucleoside triphosphates present in the reaction mixture is labeled, the newly synthesized strands will become labeled by the incorporation of the labeled nucleotides. The end product of this reaction is a mixture of unlabeled (template) and labeled... 

RAR-RXR heterodimeric complexes bind to a directly repeated, hexanucleotide motif of the consensus sequence 5 -PuGGTCA-3 (where Pu represents a purine, see above). Directly repeated response elements, in contrast to inverted repeats, are not symmetrical, and this renders the microenvironment of each half-site distinct (38). This situation implies that the orientation of RAR-RXR complexes RAREs may be ordered and occur in a non-random manner. Indeed, this is the case Perl-mann and colleagues used biochemical tech-... 

Random hexanucleotides, which bind different complementary sites on the RNA template. 

If we assume equimolar proportions and random distribution for the four nucleotides in DNA, a particular sequence should occur every 256 (4 ) for the tetranucleotide or 4096 (4 ) for die hexanucleotide. Therefore the fragments generated by the four-cutter and six-cutter enzymes should average about 250 bp and 4000 bp in length respectively. 

B. Random Hexanucleotide Priming, (various modifications of Feinberg Vogelstein 1983, Anal. Biochem. 132 6-13 Feinberg Vogelstein 1984, Anal. Biochem. 137 266). 

Production of DNA Hybridization Probes with Digoxigenin-Modified Nucleotides by Random Hexanucleotide Priming... 

Solution C Add 555 pL sterile distilled water to 50 U of random hexanucleotides (Pharmacia, Uppsala, Sweden). 

One of the most commonly used methods to detect host-cell DNA is quantitative polymerase chain reaction (qPCR), using random oligonucleotides (typically hexanucleotides) that will amplify the presence of low level host-cell genomic DNA fragments. This method may be used to detect and quantify host-cell DNA in in-process samples and the final drug substance. 

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