Sequences necessary for nucleolar targeting were identified in Box C/D small nucleolar RNAs (snoRNAs) by fluorescence microscopy. Nucleolar preparations were examined after injecting fluorescein-labelled wild-type and mutated U14 or U8 snoRNA into Xenopus oocyte nuclei. Regions in U14 snoRNA that are complementary to 18S rRNA and necessary for rRNA processing and methylation are not required fo...

Histones are the major protein component of chromatin structure. The histone family is made up of a quintet of proteins, four core histones (H2A, H2B, H3 & H4) and the linker histones (H1). Spacers are found between the coding regions. Among insects this quintet of genes is usually clustered and the clusters are tandemly repeated. Ribosomal DNA contains a cluster of the rRNA sequences 18S, 5.8S...

A recessive temperature sensitive mutant has been isolated that is defective in ribosomal RNA processing. By Northern analysis, this mutant was found to accumulate three novel rRNA species: 23S', 18S' and 7S', each of which contains sequences from the spacer region between 25S and 18S rRNA. 35S pre-rRNA accumulates, while the level of the 20S and 27S rRNA processing intermediates is depressed. ...

Eight strains of Saccharomycopsis species were examined for their partial base sequences of 18S and 26S rRNAs. The base sequences on the fingerprint segment showed three kinds of ACUAU, UCUAU, and AUAU. In the partial base sequences (positions 1451-1618, 168 bases) of 18S rRNA, all the strains of Saccharomycopsis species examined had 1-0 base difference except for the strains of Saccharomycopsi...

Mutations at position C1054 of 16S rRNA have previously been shown to cause translational suppression in Escherichia coli. To examine the effects of similar mutations in a eukaryote, all three possible base substitutions and a base deletion were generated at the position of Saccharomyces cerevisiae 18S rRNA corresponding to E. coli C1054. In yeast, as in E. coli, both C1054A (rdn-1A) and C1054G...

Plasmid pBG 35 contains the whole rDNA unit from flax (Linum usitatissimum L.) (Goldsbrough and Cullis, 1981). We cloned four different Eco RI restriction rDNA fragments of pBG 35 in the plasmid vector pBluescript SK+ (pBS). One of the subclones (p2.1) contained the most part of the 5 ́-end of 18S rRNA gene (1581 bp) and was used as a heterologous DNA probe in molecular hybridization experiments...

Re-examination of the holotype of Burmoniscus kitadaitoensis Nunomura, 2009 from Kitadaitojima Island, southern Japan reveals that this species is a junior synonym of B. meeusei (Holthuis, 1947). Partial regions of mitochondrial COI, 12S and 16S rRNA genes, and nuclear 18S and 28S rRNA genes were detected for species identification in the future.

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...

Previous analyses of complexes of 40S ribosomal subunits with the hepatitis C virus (HCV) internal ribosome entry site (IRES) have revealed contacts made by the IRES with ribosomal proteins. Here, using chemical probing, we show that the HCV IRES also contacts the backbone and bases of the CCC triplet in the 18S ribosomal RNA (rRNA) expansion segment 7. These contacts presumably provide interpl...