title: Cytotoxicity of ribosome-inactivating protein saporin is not mediated through alpha2-macroglobulin receptor.
abstract: Saporin is a single chain ribosome-inactivating protein produced by the plant Saponaria officinalis. Several isoforms of saporin have been isolated from various parts of the plant. In the present study recombinant saporin isoforms 5 and 6 were produced in Escherichia coli. Saporin-6 was found to be more active than saporin-5 in its N-glycosidase, cytotoxic, and genomic DNA fragmentation activities. Earlier, saporin has been shown to bind low-density lipoprotein receptor-related protein (LRP), however, in this study the sensitivities of LRP-negative and LRP-positive cell lines were found to be similar towards saporin-6 toxicity suggesting the internalization of saporin not to be solely dependent on the expression of LRP on eukaryotic cells.
authors.affiliation: Immunochemistry Laboratory, National Institute of Immunology, New Delhi, India.
authors.forename: Shveta
authors.initials: S
authors.lastname: Bagga
authors.forename: M V
authors.initials: MV
authors.lastname: Hosur
authors.forename: Janendra K
authors.initials: JK
authors.lastname: Batra
mesh_terms: D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D053938:DNA Fragmentation; D000922:Immunotoxins / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D026503:Low Density Lipoprotein Receptor-Related Protein-1 / Q000502:physiology*; D009699:N-Glycosyl Hydrolases / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D020033:Protein Isoforms / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity; D011500:Protein Synthesis Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D054789:Ribosome Inactivating Proteins, Type 1; D012270:Ribosomes / Q000187:drug effects; D000076985:Saporins
chemical_list: D000922:Immunotoxins; D026503:Low Density Lipoprotein Receptor-Related Protein-1; D010940:Plant Proteins; D020033:Protein Isoforms; D011500:Protein Synthesis Inhibitors; D054789:Ribosome Inactivating Proteins, Type 1; D009699:N-Glycosyl Hydrolases; D000076985:Saporins