Giardia lamblia telomeres have been isolated from a library enriched for repaired chromosome ends by (i) screening with a Plasmodium falciparum telomere and (ii) differential hybridization with Bal 31-digested and total G. lamblia DNA. Analysis of three clones isolated by this strategy has identified multiple tandem repeats of the 5-mer TAGGG. An oligonucleotide containing these repeats recogni...

BACKGROUND AND AIMS The Brassicaceae family encompasses numerous species of great agronomic importance, belonging to such genera, as Brassica, Raphanus, Sinapis and Armoracia. Many of them are characterized by extensive intraspecific diversity of phenotypes. The present study focuses on the polymorphism of number, appearance and chromosomal localization of ribosomal DNA (rDNA) sites and, when p...

rDNA loci, composed of hundreds of tandemly duplicated arrays of rRNA genes, are known to be among the most unstable genetic elements due to their repetitive nature. rDNA instability underlies aging (replicative senescence) in yeast cells, however, its contribution to the aging of multicellular organisms is poorly understood. In this study, we investigate the dynamics of rDNA loci during aging ...

Chromatin domain organization and the compartmentalized distribution of chromosomal regions are essential for packaging of deoxyribonucleic acid (DNA) in the eukaryotic nucleus as well as regulated gene expression. Nucleoli are the most prominent morphological structures of cell nuclei and nucleolar organization is coupled to cell growth. It has been shown that nuclear scaffold/matrix attachmen...

Leptospirosis, a disease with protean manifestations, is caused by Leptospira species complex. A definite diagnosis of leptospirosis during the first week of the illness is a major challenge to investigating clinical laboratories. PCR is a rapid, sensitive and specific means of diagnosing Leptospira infections in the early phase of the disease. In this study, the applicability of routine PCR as...

Abstract Twelve hyper-? carotene-producing strains of algae assigned to the genus Dunaliella salina have been isolated from various hypersaline environments in Israel, South Africa, Namibia and Spain. Intron-sizing SSU rDNA phylogenetic analysis these isolates were undertaken using four commonly employed markers for genotyping, LSU rDNA, ITS, rbc L tuf A their application study evaluated. Novel...

Irrigation with wastewater releases pharmaceuticals, pathogenic bacteria, and resistance genes, but little is known about the accumulation of these contaminants in the environment when wastewater is applied for decades. We sampled a chronosequence of soils that were variously irrigated with wastewater from zero up to 100 years in the Mezquital Valley, Mexico, and investigated the accumulation o...

The presence of inactive units in tandem arrays of ribosomal genes (rDNA) has been linked to increased transcriptional capacity, but a recent study indicates that inactive units are necessary for sister chromatid cohesion and genetic stability of rDNA.

Ribosomal RNAs (rRNAs) in budding yeast are encoded by ~100-200 repeats of a 9.1kb sequence arranged in tandem on chromosome XII, the ribosomal DNA (rDNA) locus. Copy number of rDNA repeat units in eukaryotic cells is maintained far in excess of the requirement for ribosome biogenesis. Despite the importance of the repeats for both ribosomal and non-ribosomal functions, it is currently not know...

The current study focuses on the biological diversity of two strains Antarctic diatoms (strains IMA082A and IMA088A) collected isolated from Ross Sea (Antarctica) during XXXIV Italian Expedition. Both species presented typical morphological characters genus Craspedostauros: cribrate areolae, “fore-and-aft” chloroplasts a narrow “stauros”. This classification is congruent with molecular phylogen...