Biomaterial Database

The site of action of alpha-sarcin on eukaryotic ribosomes. The sequence at the alpha-sarcin cleavage site in 28 S ribosomal ribonucleic acid. 1982

Y Endo, and I G Wool

alpha-Sarcin is a cytotoxic protein that inhibits eukaryotic elongation factor 1 catalyzed binding of aminoacyl-tRNA to eukaryotic ribosomes as a result of cleaving a fragment from the large RNA in the 60 S ribosomal subunit. Rat liver polysomes are sensitive to alpha-sarcin in vitro only if the treatment is carried out in the presence of EDTA. The oligonucleotide produced by alpha-sarcin action on rat liver ribosomes is derived from the 3' end of 28 S rRNA and has a molecular weight of approximately 161,000 (about 488 bases). The sequence at the site of cleavage (the 5' end of the oligonucleotide produced by alpha-sarcin action on rat liver ribosomes) was AGGAAC for both rat liver 28 S rRNA and yeast 25 S rRNA. Based on the size of the alpha-fragment derived from Escherichia coli ribosomes (about 243 nucleotides), it is likely that a similar sequence, AGGACC, occurs at the site of cleavage of prokaryotic 23 S rRNA. It is also likely that the sequence on the 5' side of the alpha-sarcin cleavage site is UAGUACGAG. The sequence UAGUACGAGAGGAAC must be important because it is conserved and because hydrolysis of a single phosphodiester bond there inactivates the ribosome. We suggest that this region of the large nucleic acid in the 60 S subparticle is involved in binding aminoacyl-tRNA to the ribosome, first, because it is the eukaryotic elongation factor 1 catalyzed reaction that is inhibited by alpha-sarcin, and second, because peptidyl-tRNA seems to protect polysomes against the toxin. The function of EDTA appears to be to remove peptidyl-tRNA since puromycin also sensitizes polysomes to alpha-sarcin.

UI	MeSH Term	Description	Entries
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D004587	Electrophoresis, Agar Gel	Electrophoresis in which agar or agarose gel is used as the diffusion medium.	Electrophoresis, Agarose Gel,Agar Gel Electrophoresis,Agarose Gel Electrophoresis,Gel Electrophoresis, Agar,Gel Electrophoresis, Agarose
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D004722	Endoribonucleases	A family of enzymes that catalyze the endonucleolytic cleavage of RNA. It includes EC 3.1.26.-, EC 3.1.27.-, EC 3.1.30.-, and EC 3.1.31.-.	Endoribonuclease
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D005656	Fungal Proteins	Proteins found in any species of fungus.	Fungal Gene Products,Fungal Gene Proteins,Fungal Peptides,Gene Products, Fungal,Yeast Proteins,Gene Proteins, Fungal,Peptides, Fungal,Proteins, Fungal
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
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
D012270	Ribosomes	Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.	Ribosome