title: Ribotoxins and their applications in probing the topographical structure of ribosomes.
abstract: Ribotoxins are a group of ribosome-inactivating proteins (RIPs) isolated mostly from plants. They inactivate ribosomes by a mechanism as RNA N-glycosidase that removes a specific adenine base from the highly conserved "S/R domain" in the largest ribosomal RNA. In this review, we introduce the major results from our laboratory in recent years on the study of the structure and function of RIPs and ribosomes: [1] Purification and characterization of the enzymatic mechanism of RIPs. Several new RIPs were purified and their RNA N-glycosidase and supercoil-dependent DNA endonuclease activities were studied. [2] The topographical structure of ribosomes. The relationship between the structure and function of ribosomes, especially of the "S/R domain" in rat 28S rRNA, were investigated by means of RIPs and other chemical probes. [3] The cytotoxicity of two RIPs to carcinoma cells. [4] Several new methods for studying RIPs and probing the structure of ribosomes were developed, i.e., radioassays for RNA N-glycosidase, glycoprotein detection by fluorescent labeling on SDS-polyacrylamide gels, and methods for small RNA sequencing.
authors.affiliation: Shanghai Institute of Biochemistry, Academia Sinica, China. liuwy@sunm.shcnc.ac.cn
authors.forename: W Y
authors.initials: WY
authors.lastname: Liu
authors.forename: Z
authors.initials: Z
authors.lastname: Pu
mesh_terms: D000818:Animals; D003850:Deoxyribonuclease I / Q000494:pharmacology; D009699:N-Glycosyl Hydrolases / Q000494:pharmacology; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D012335:RNA, Ribosomal / Q000037:antagonists & inhibitors*; D012339:RNA, Ribosomal, 28S / Q000037:antagonists & inhibitors / Q000737:chemistry; D054788:Ribosome Inactivating Proteins; D012270:Ribosomes / Q000378:metabolism / Q000648:ultrastructure*; D014118:Toxins, Biological / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D010936:Plant Extracts; D012335:RNA, Ribosomal; D012339:RNA, Ribosomal, 28S; D014118:Toxins, Biological; D003850:Deoxyribonuclease I; D009699:N-Glycosyl Hydrolases; D054788:Ribosome Inactivating Proteins