Biomaterial Database

Fidelity of synthesis of preribosomal RNA in isolated nucleoli and nucleolar chromatin. 1977

N R Ballal, and Y C Choi, and R Mouche, and H Busche

Comparisons were made of the T1 ribonuclease digests of 32P-labeled nucleolar 45S RNA of intact Novikoff hepatoma cells and the RNA synthesized in vitro by isolated nucleoli. Approximately 200 oligonucleotide spots were found in the two-dimensional chromatogram of 45S nucleolar RNA labeled in vivo, which includes fragments of 18S and 28S rRNA and nonconserved spacer regions; four spots containing 2'-O-methyl nucleotides were not found in the corresponding pattern of RNA labeled in vitro. This high degree of fidelity was retained in the patterns of spots from the RNA produced with nucleolar chromatin as template. This specific expression of rDNA was lost when the nucleolar chromatin was completely deproteinized. Specific spots found in the control patterns were absent and many nonspecific oligonucleotides were found to be labeled. A similar nonspecific chromatogram pattern was found when nucleolar chromatin was transcribed with RNA polymerase (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6) of Escherichia coli. These results show that specificity of genetic expression in vitro of isolated chromatin of eukaryotic systems is dependent on the chromatin-associated proteins and the type of RNA polymerase present.

UI	MeSH Term	Description	Entries
D008113	Liver Neoplasms	Tumors or cancer of the LIVER.	Cancer of Liver,Hepatic Cancer,Liver Cancer,Cancer of the Liver,Cancer, Hepatocellular,Hepatic Neoplasms,Hepatocellular Cancer,Neoplasms, Hepatic,Neoplasms, Liver,Cancer, Hepatic,Cancer, Liver,Cancers, Hepatic,Cancers, Hepatocellular,Cancers, Liver,Hepatic Cancers,Hepatic Neoplasm,Hepatocellular Cancers,Liver Cancers,Liver Neoplasm,Neoplasm, Hepatic,Neoplasm, Liver
D009374	Neoplasms, Experimental	Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.	Experimental Neoplasms,Experimental Neoplasm,Neoplasm, Experimental
D009694	Nucleic Acid Precursors	Use for nucleic acid precursors in general or for which there is no specific heading.	Acid Precursors, Nucleic,Precursors, Nucleic Acid
D009843	Oligoribonucleotides	A group of ribonucleotides (up to 12) in which the phosphate residues of each ribonucleotide act as bridges in forming diester linkages between the ribose moieties.
D002466	Cell Nucleolus	Within most types of eukaryotic CELL NUCLEUS, a distinct region, not delimited by a membrane, in which some species of rRNA (RNA, RIBOSOMAL) are synthesized and assembled into ribonucleoprotein subunits of ribosomes. In the nucleolus rRNA is transcribed from a nucleolar organizer, i.e., a group of tandemly repeated chromosomal genes which encode rRNA and which are transcribed by RNA polymerase I. (Singleton & Sainsbury, Dictionary of Microbiology & Molecular Biology, 2d ed)	Plasmosome,Cell Nucleoli,Nucleoli, Cell,Nucleolus, Cell,Plasmosomes
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
D006163	Ribonuclease T1	An enzyme catalyzing the endonucleolytic cleavage of RNA at the 3'-position of a guanylate residue. EC 3.1.27.3.	Guanyloribonuclease,RNase T1,Ribonuclease N1,Aspergillus oryzae Ribonuclease,Guanyl-Specific RNase,RNase Apl,RNase F1,RNase Pch 1,RNase ST,Ribonuclease F1,Ribonuclease F2,Ribonuclease ST,Ribonuclease T-1,T 1 RNase,Guanyl Specific RNase,RNase, Guanyl-Specific,RNase, T 1,Ribonuclease T 1,Ribonuclease, Aspergillus oryzae
D006528	Carcinoma, Hepatocellular	A primary malignant neoplasm of epithelial liver cells. It ranges from a well-differentiated tumor with EPITHELIAL CELLS indistinguishable from normal HEPATOCYTES to a poorly differentiated neoplasm. The cells may be uniform or markedly pleomorphic, or form GIANT CELLS. Several classification schemes have been suggested.	Hepatocellular Carcinoma,Hepatoma,Liver Cancer, Adult,Liver Cell Carcinoma,Liver Cell Carcinoma, Adult,Adult Liver Cancer,Adult Liver Cancers,Cancer, Adult Liver,Cancers, Adult Liver,Carcinoma, Liver Cell,Carcinomas, Hepatocellular,Carcinomas, Liver Cell,Cell Carcinoma, Liver,Cell Carcinomas, Liver,Hepatocellular Carcinomas,Hepatomas,Liver Cancers, Adult,Liver Cell Carcinomas
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA
D012335	RNA, Ribosomal	The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)	Ribosomal RNA,15S RNA,RNA, 15S