Results 271 to 280 of about 80,041 (307)

Nuclear retention of 18S ribosomal RNA by human myeloma cells

Cell and Tissue Research, 1979
Normal quiescent lymphocytes regulate their ribosome content by selectively degrading newly synthesized 18S ribosomal RNA. Unlike actively dividing HeLa cells, lymphocytes retain 18S ribosomal RNA in the nucleus after synthesis instead of immediately transporting it to the cytoplasm.
J W, Bynum, E, Volkin
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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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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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18S Ribosomal RNA Gene Sequences of Cochliopodium (Himatismenida) and the Phylogeny of Amoebozoa

Protist, 2005
Cochliopodium is a very distinctive genus of discoid amoebae covered by a dorsal tectum of carbohydrate microscales. Its phylogenetic position is unclear, since although sharing many features with naked "gymnamoebae", the tectum sets it apart. We sequenced 18S ribosomal RNA genes from three Cochliopodium species (minus, spiniferum and Cochliopodium sp.,
Alexander, Kudryavtsev, Detlef, Bernhard, Martin, Schlegel, Ema E Y, Chao, Thomas, Cavalier-Smith   +4 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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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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Studies on the role of 23 s nucleolar RNA as an intermediate in the synthesis of 18 s ribosomal RNA

Journal of Molecular Biology, 1971
Abstract From whole nucleolar RNA of Novikoff hepatoma cells, a single symmetrical peak of 23 s RNA was obtained by repeated sucrose density-gradient centrifugations. Hybridization experiments showed that nucleolar 23 s RNA is composed of 18 s ribosomal RNA and other RNA segments.
K, Egawa, Y C, Choi, H, Busch
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The human 18S ribosomal RNA gene: evolution and stability.

American journal of human genetics, 1986
We report the 1,870-base-pair primary sequence of a human 18S rRNA gene and propose a secondary structure based on this sequence and the general mammalian structure. A basic secondary structure for the small subunit rRNA has been preserved throughout evolution by compensatory and neutral base changes in double-stranded regions.
I L, Gonzalez, R D, Schmickel
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