The present study characterized Argulus spp. infecting the cultured carps using 18S rRNA gene sequences, estimated the genetic similarity among Argulus spp. and established their phylogenetic relationship. Of the 320 fish samples screened, 34 fish (10.6%) had Argulus infection. The parasitic frequency index (PFI) was observed to be high (20%) in Hypophthalmichthys molitrix and Labeo bata. The f...

Molecular tools have revolutionized the exploration of biodiversity, especially in organisms for which traditional taxonomy is difficult (Tang et al., 2012). The small subunit (SSU) 18S rRNA gene is one of the most frequently used genes in phylogenetic studies and an important marker for random target PCR in environmental biodiversity screening. 18S rDNA is a nuclear ribosomal gene, commonly re...

The DNA sequence of the intragenic region of the rat 45S ribosomal RNA precursor was determined. This sequence contains 2282 nucleotides and extends from the conserved EcoR I site near the 3' terminus of 18S rRNA to 69 nucleotides downstream of the 5' terminus of 28S rRNA. The sequences corresponding to 18S and 5.8S rRNA were identified by comparison with previously published data. The 5' termi...

Three small nucleolar RNAs (snoRNAs), E1, E2 and E3, have been described that have unique sequences and interact directly with unique segments of pre-rRNA in vivo. In this report, injection of antisense oligodeoxynucleotides into Xenopus laevis oocytes was used to target the specific degradation of these snoRNAs. Specific disruptions of pre-rRNA processing were then observed, which were reverse...

Bugs (Insecta: Heteroptera) are frequently used as examples of unusual cytogenetic characters, and the family Cimicidae is one of most interest in this respect. We have performed a cytogenetic study of the common bed bug Cimex lectularius Linnaeus, 1758 using both classical (Schiff-Giemsa and AgNO3-staining) and molecular cytogenetic techniques (base-specifi c DAPI/CMA3 fl uorochromes and FISH ...

The circadian regulation of gene expression allows plants and animals to anticipate predictable environmental changes. While the influence of the circadian clock has recently been shown to extend to ribosome biogenesis, the dynamics and regulation of the many small nucleolar RNA that are required in pre-ribosomal RNA folding and modification are unknown. Using a novel computational method, we s...

The quantitative real-time polymerase chain reaction (qRT-PCR) is one of the most widely used methods to study gene expression profiles, and it requires appropriate normalization for accurate and reliable results. Although several genes are commonly used as reference genes (such as GAPDH, ACTB, and 18S rRNA), they are also regulated and can be expressed at varying levels. In this study, we eval...