title: Inefficient serotype knock down leads to stable coexistence of different surface antigens on the outer membrane in Paramecium tetraurelia.
abstract: Expression of surface antigens is usually mutually exclusive, meaning that only one protein is present on the cell surface. With the RNAi feeding technology we induce serotype shifts in Paramecium tetraurelia which are demonstrated to be incomplete, meaning that the cells remain in a shifting state. The coexpression of "old" and "new" protein on the surface can be detected to be stable for more than 15 divisions over a 5-day feeding procedure, a time period different from that reported for temperature-induced shifts. A characteristic heterogenic distribution of the different surface antigens is demonstrated by double indirect-immunofluorescent-staining and we show antigen transport mechanisms related to the tips of cilia. Therefore, we discuss release mechanisms, potential sorting mechanisms for glycosylphosphatidylinositol-anchored proteins and the localizations of surface antigens, which are important for the reported classical immobilization reaction.
authors.affiliation: Department of Biology, Division of Ecology, University of Kaiserslautern, Erwin-Schrödinger-Street, Kaiserslautern, Germany. msimon@rhrk.uni-kl.de
authors.forename: Martin C
authors.initials: MC
authors.lastname: Simon
authors.forename: Simone
authors.initials: S
authors.lastname: Marker
authors.forename: Helmut J
authors.initials: HJ
authors.lastname: Schmidt
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000378:metabolism; D000953:Antigens, Protozoan / Q000096:biosynthesis* / Q000502:physiology; D000954:Antigens, Surface / Q000096:biosynthesis / Q000502:physiology; D019084:Fluorescent Antibody Technique, Indirect; D015870:Gene Expression / Q000502:physiology*; D007150:Immunohistochemistry / Q000379:methods; D016805:Paramecium tetraurelia / Q000145:classification / Q000235:genetics / Q000276:immunology*; D034622:RNA Interference / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012703:Serotyping
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D000954:Antigens, Surface