Restriction endonuclease cleavage analyses of cloned and genomic DNA samples indicate that the structure of the DNA encoding the large cytoplasmic RNAs (rDNAs) is altered in Drosophila mercatorum lines which exhibit an abnormal abdomen (aa) phenotype. In a majority of the rDNA repeat units from aa flies, the 28S coding sequence is interrupted by a large [5-6 kilobase pairs (kbp)] insert. A subc...

This paper examines the effects of DNA sequence evolution on RNA secondary structures and compensatory mutations. Models of the secondary structures of Drosophila melanogaster 18S ribosomal RNA (rRNA) and of the complex between 2S, 5.8S, and 28S rRNAs have been drawn on the basis of comparative and energetic criteria. The overall AU richness of the D. melanogaster rRNAs allows the resolution of...

We have determined the nucleotide sequence of part of a cloned ribosomal transcription unit from Xenopus laevis extending from the 3' region of the 18S gene through the 18S-28S intergene region into the start of the 28S gene. The 18S 3' region possess two tracts of high homology with the corresponding segments of other eukaryotic 18S genes (yeast and Bombyx mori) separated by a tract of low hom...

We used morphological and molecular approaches to evaluate the diversity of free-living marine nematodes (order Enoplida) at four coastal sites in the Gulf of California and three on the Pacific coast of Baja California, Mexico. We identified 22 morphological species belonging to six families, of which Thoracostomopsidae and Oncholaimidae were the most diverse. The genus Mesacanthion (Thoracost...

In the present study, a novel broad-range real-time PCR was developed for the rapid detection of human pathogenic fungi. The assay targets a part of the 28S large-subunit ribosomal RNA (rDNA) gene. We investigated its application for the most important human pathogenic fungal genera, including Aspergillus, Candida, Cryptococcus, Mucor, Penicillium, Pichia, Microsporum, Trichophyton, and Scopula...

Oscheius onirici sp. n. (Nematoda: Rhabditidae) was isolated from a karst cave soil of Central Italy. Molecular and morphological analyses were performed. Total DNA was extracted from individual nematodes and the mitochondrial COI, the ITS containing region, the D2-D3 expansion domains of the 28S rRNA gene and the 18S rRNA gene were amplified and sequenced. BLAST search at NCBI by using all mol...

We report on digitate and capitate Octocorallia within the genera Parasphaerasclera McFadden & Ofwegen, 2013, Eleutherobia Pütter, 1900, Sphaerasclera McFadden & Ofwegen, 2013, and Paraminabea Williams & Alderslade, 1999 from tropical Western Australian waters. Three new species (Parasphaerasclera kimberleyensis, Eleutherobia australiensis, Eleutherobia imaharai) are described, with a discussio...

R1Bm is a long interspersed element (LINE) inserted into a specific sequence within 28S rDNA of the silkworm genome. Of two open reading frames (ORFs) of R1Bm, ORF2 encodes a reverse transcriptase (RT) and an endonuclease (EN) domain which digests specifically both top and bottom strand of the target sequence in 28S rDNA. To elucidate the sequence specificity of EN domain of R1Bm (R1Bm EN), we ...

In the material recently collected in Madeira, 16 species of ptyctimous mites have been found. A new species of Austrophthiracarus rabacalensis Niedbala sp. nov. has been described. The presence of P. globosus and S. (R.) ortizi, reported earlier from Madeira has not been confirmed, but P. anonymus and P. montanus, so far not reported from this island, have been found. All 16 species identified...

Entomopathogenic nematodes in Steinernema, together with their symbiont bacteria Xenorhabdus, are obligate and lethal parasites of insects that can provide effective biological control of some important lepidopteran, dipteran, and coleopteran pests of commercial crops. Phylogenetic relationships among 21 Steinernema species were estimated using 28S ribosomal DNA (rDNA) sequences and morphologic...