BIOMAT Database Logo BIOMAT Database Logo

RNA N-glycosidase activity of ricin A-chain. Mechanism of action of the toxic lectin ricin on eukaryotic ribosomes. 1987

Y Endo, and K Tsurugi

The modification reaction of 28 S rRNA in eukaryotic ribosomes by ricin A-chain was characterized. To examine whether ricin A-chain release any bases from 28 S rRNA, rat liver ribosomes were incubated with a catalytic amount of the toxin, and a fraction containing free bases and nucleosides was prepared from the postribosomal fraction of the reaction mixture by means of ion-exchange column chromatography. Thin-layer chromatographic analysis of this fraction revealed a release of 1 mol of adenine from 1 mol of ribosome. When the ribosomes or naked total RNAs were treated with ricin A-chain in the presence of [32P] phosphate, little incorporation of the radioactivity into 28 S rRNA was observed, indicating that the release is not mediated by phosphorolysis. Thus, considering together with the previous result (Endo, Y., Mitsui, K., Motizuki, M., and Tsurugi, K. (1987) J. Biol. Chem. 262, 5908-5912), the results in the present experiments demonstrated that ricin A-chain inactivates the ribosomes by cleaving the N-glycosidic bond of A4324 of 28 S rRNA in a hydrolytic fashion.

UI MeSH Term Description Entries
D007700 Kinetics The rate dynamics in chemical or physical systems.
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
D009708 Nucleotidases A class of enzymes that catalyze the conversion of a nucleotide and water to a nucleoside and orthophosphate. EC 3.1.3.-.
D010766 Phosphorylation The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety. Phosphorylations
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
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
D012276 Ricin A protein phytotoxin from the seeds of Ricinus communis, the castor oil plant. It agglutinates cells, is proteolytic, and causes lethal inflammation and hemorrhage if taken internally. Castor Bean Lectin,Lectin, Castor Bean,Lectin, Ricinus,Ricin Toxin,RCA 60,RCA60,Ricin A Chain,Ricin B Chain,Ricin D,Ricin I,Ricinus Toxin,A Chain, Ricin,B Chain, Ricin,Ricinus Lectin,Toxin, Ricin,Toxin, Ricinus
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
D051381 Rats The common name for the genus Rattus. Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus

Related Publications

Y Endo, and K Tsurugi
The mechanism of action of trichosanthin on eukaryotic ribosomes--RNA N-glycosidase activity of the cytotoxin.
March 1992, Nucleic acids research,
Y Endo, and K Tsurugi
Alpha-sarcin impairs the N-glycosidase activity of ricin on ribosomes.
April 1989, Biochemical and biophysical research communications,
Y Endo, and K Tsurugi
THE action of ricin A-chain on ribosomes.
September 1982, Biochemical and biophysical research communications,
Y Endo, and K Tsurugi
Effects of chemical modification of arginine residues outside the active site cleft of ricin A-chain on its RNA N-glycosidase activity for ribosomes.
April 1994, Bioscience, biotechnology, and biochemistry,
Y Endo, and K Tsurugi
Mechanism of action of ricin and related toxins on the inactivation of eukaryotic ribosomes.
January 1988, Cancer treatment and research,
Y Endo, and K Tsurugi
[The mechanisms of action of the cytotoxic proteins, alpha-sarcin and ricin A-chain on eukaryotic ribosomes].
October 1989, Seikagaku. The Journal of Japanese Biochemical Society,
Y Endo, and K Tsurugi
The structure and action of ricin, a cytotoxic N-glycosidase.
February 1991, Seminars in cell biology,
Y Endo, and K Tsurugi
The effects of N-glycosylation on the lectin activity of recombinant ricin B chain.
June 1991, Carbohydrate research,
Y Endo, and K Tsurugi
Some observations on the mechanism of toxic action of ricin.
November 1950, The Journal of pharmacology and experimental therapeutics,
Y Endo, and K Tsurugi
Protection and rescue of ribosomes from the action of ricin A chain.
June 1979, Biochemistry,
Copied contents to your clipboard!