Results 301 to 310 of about 81,162 (322)

Systematics of Holometabolous Insect Orders Based on 18S Ribosomal RNA

Molecular Phylogenetics and Evolution, 1993
Phylogenetic relationships of 19 species representing nine holometabolous insect orders and three outgroup orders were examined using sequence data from two-thirds of the 18S nuclear ribosomal RNA molecule. Of 1330 aligned nucleotide sites in 19 taxa, 460 were variable and used for phylogenetic analysis.
D P, Pashley, B A, McPheron, E A, Zimmer
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18 S Ribosomal RNA Is Degraded during Ribosome Maturation in Irradiated HeLa Cells

Radiation Research, 1989
The effects of ionizing radiation (137Cs) on processing of ribosomal RNA (rRNA) were studied by pulse-labeling HeLa S3 cells with [3H]uridine immediately prior to irradiation. The 45 S rRNA precursor, and its two major daughter species, 28 and 18 S rRNA, were separated by gel electrophoresis and the extent of radiolabel incorporation into each was ...
J M, Krolak, D, McClain, S L, Snyder, P, Fuchs, K W, Minton   +4 more
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Requirement for intron-encoded U22 small nucleolar RNA in 18S ribosomal RNA maturation

Science, 1994
The nucleoli of vertebrate cells contain a number of small RNAs that are generated by the processing of intron fragments of protein-coding gene transcripts. The host gene (UHG) for intro-encoded human U22 is unusual in that it specifies a polyadenylated but apparently noncoding RNA.
K T, Tycowski, M D, Shu, J A, Steitz
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Phylogenetic position of Heronimus mollis (digenea): Evidence from 18S ribosomal RNA

International Journal for Parasitology, 1993
Most (1918bp) of the nucleotide sequence of the 18S ribosomal RNA gene of Heronimus mollis was determined. We aligned this sequence with 18S rRNA sequences from 7 other digeneans and an aspidobothrean. Using these data we explored the phylogenetic position of H. mollis. No support was found for the hypothesis that H.
Barker, S. C., Blair, D., Cribb, T. H., Tonion, K.   +3 more
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A large nucleolar U3 ribonucleoprotein required for 18S ribosomal RNA biogenesis

Nature, 2002
Although the U3 small nucleolar RNA (snoRNA), a member of the box C/D class of snoRNAs, was identified with the spliceosomal small nuclear RNAs (snRNAs) over 30 years ago, its function and its associated protein components have remained more elusive. The U3 snoRNA is ubiquitous in eukaryotes and is required for nucleolar processing of pre-18S ribosomal
François, Dragon, Jennifer E G, Gallagher, Patricia A, Compagnone-Post, Brianna M, Mitchell, Kara A, Porwancher, Karen A, Wehner, Steven, Wormsley, Robert E, Settlage, Jeffrey, Shabanowitz, Yvonne, Osheim, Ann L, Beyer, Donald F, Hunt, Susan J, Baserga   +12 more
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In vitro transcription of ribosomal RNA on phage λrifd 18 DNA

Biochimica et Biophysica Acta (BBA) - Nucleic Acids and Protein Synthesis, 1978
In vitro transcription of ribosomal RNA was studied on the DNA of the transducing bacteriphage lambdarifd 18, which carries an rRNA transcription unit from Escherichia coli. rRNA synthesis was preferential at all polymerase/DNA ratios tested, and at the optimal 0.3 weight ratio nearly 60% of the transcript was rRNA.
I, Kiss, K, Slaska, J, Sümegi, A, Udvardy, P, Venetianer   +4 more
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Differential inhibition of 28s and 18s ribosomal RNA synthesis by actinomycin

Biochemical and Biophysical Research Communications, 1969
Abstract Low doses of actinomycin inhibit the synthesis of 28s ribosomal RNA to a greater extent than 18s ribosomal RNA in phytohaemagglutinin stimulated lymphocytes. Under these conditions the excess 18s RNA continues to enter the cytoplasm for extended periods.
J E, Kay, H L, Cooper
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Thermodynamics of the pseudo‐knot in helix 18 of 16S ribosomal RNA

Biopolymers, 2018
AbstractA fragment of E. coli 16S rRNA formed by nucleotides 500 to 545 is termed helix 18. Nucleotides 505‐507 and 524‐526 form a pseudo‐knot and its distortion affects ribosome function. Helix 18 isolated from the ribosome context is thus an interesting fragment to investigate the structural properties and folding of RNA with pseudo‐knots.
Monika Wojciechowska, Marta Dudek, Joanna Trylska   +2 more
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Nucleotide sequence of Xenopus laevis 18S ribosomal RNA inferred from gene sequence

Nature, 1981
18S ribosomal RNA in Xenopus laevis is 1,825 nucleotides long, as inferred from sequence analysis of an 18S gene. All the 40 rRNA methyl groups can be located in the sequence. Comparison with the yeast (Saccharomyces cerevisiae) 18S sequence reveals extensive regions of high homology interspersed with tracts having little or no homology.
M, Salim, B E, Maden
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Probing the Secondary Structure of Expansion Segment ES6 in 18S Ribosomal RNA

Biochemistry, 2006
Expansion segment ES6 in 18S ribosomal RNA is, unlike many other expansion segments, present in all eukaryotes. The available data suggest that ES6 is located on the surface of the small ribosomal subunit. Here we have analyzed the secondary structure of the complete ES6 sequence in intact ribosomes from three eukaryotes, wheat, yeast, and mouse ...
Gunnar, Alkemar, Odd, Nygård
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