The rDNA genes coding for ribosomal RNA (rRNA) in animals are repeat sequences with high GC content and complicated structure. Based on the sequences of human ribosomal DNA repeat unit and transcription unit and the long and accurate PCR method with LA Taq DNA polymerase and GC buffer, we were able to amplify the complicated repeat sequences of rDNA genes in Bos taurus. Three rDNA genes and 2 i...

To the Editor—In a recent article, Jiang et al [1] showed that blood levels of bacterial DNA, as determined by quantitative polymerase chain reaction (PCR) on 16S ribosomal DNA fragments, were significantly higher in human immunodefi-ciency virus (HIV)–infected patients than were those in uninfected control patients. Moreover, the level of bacterial DNA in the blood was shown to decrease after ...

This study represents phylogenetic analyses of two woody polygonaceous genera Calligonum and Pteropyrum using both chloroplast fragment (trnL-F) and the nuclear ribosomal internal transcribed spacer (nrDNA ITS) sequence data. All inferred phylogenies using parsimony and Bayesian methods showed that Calligonum and Pteropyrum are both monophyletic and closely related taxa. They have no affinity w...

We have amplified and sequenced the 5.8S and 28S ribosomal DNA genes and intergenic regions of Paracoccidioides brasiliensis, strain Pb01. Using primers specifically designed for both ribosomal DNA regions, we were able to discriminate between P. brasiliensis and other human pathogenic fungi by PCR. The use of this molecular marker could be important for paracoccidiodomycosis diagnosis and ecol...

Fungi are ubiquitous and their spores found in the air outside within built environment. We investigated fungal species present a teaching laboratory at Shepherd University. Airborne fungi were captured passively three sites on two different culture media. Viable isolated to pure then identified by DNA barcode using internal transcribed spacer region of ribosomal DNA. Twenty-four isolates order...

Genetic variability of the nontranscribed spacer (NTS) region within ribosomal DNA repeating units in the various subspecies of Mus musculus was determined. Mice belonging to several laboratory mouse strains were examined by means of Southern blot hybridization with a mouse ribosomal DNA probe. This probe encompasses the 3' end of the 28S ribosomal RNA (rRNA) gene and the following spacer. Rest...

Larvae and pupae representing four genera of aquatic dance flies, Chelifera Macquart, Hemerodromia Meigen, Metachela Coquillett, and Neoplasta Coquillett (Diptera: Empididae: Hemerodromiinae) are differentiated, diagnosed, illustrated, and keyed. Results are based on: limited rearing associations of larvae, pupae, and adults; external morphology of larvae, pupae, and pupal exuviae; and fragment...

The polymerase chain reaction and hybridization to genomic blots were used to investigate whether the previously observed inclusion of 5S ribosomal RNA genes in the 28S-18S ribosomal DNA intergenic regions of some crustacean species (copepods) could also be detected in other arthropods. Such an arrangement was found not only in other calanoid copepod species but also in a cirriped, an euphausid...