title: Cytochemical features common to nucleoli and cytoplasmic nucleoloids of Olea europaea meiocytes: detection of rRNA by in situ hybridization.
abstract: We used light and electron microscopic techniques to study the composition of cytoplasmic nucleoloids during meiotic division in Olea europaea. Nucleoloids were found in two clearly distinguishable morphological varieties: one similar in morphology to the nucleolus, and composed mainly of dense fibrillar component, and another surrounded by many ribosome-like particles. Cytochemical and immunocytochemical techniques showed similar reactivities in nucleoloids and the nucleolus: both are ribonucleoproteic in nature, and possess argyrophillic, argentaffinic and highly phosphorylated proteins. Immunohistochemical techniques failed to detect DNA in either structure. In situ hybridization to a 18 S rRNA probe demonstrated the presence of ribosomal transcripts in both the nucleolus and nucleoloids. These similarities in morphology and composition may reflect similar functionalities.
authors.affiliation: Plant Biochemistry, Molecular and Cellular Biology Department, Estación Experimental del Zaidín, CSIC, Granada, Spain.
authors.forename: J D
authors.initials: JD
authors.lastname: Alché
authors.forename: M C
authors.initials: MC
authors.lastname: Fernández
authors.forename: M I
authors.initials: MI
authors.lastname: Rodríguez-García
mesh_terms: D002466:Cell Nucleolus / Q000378:metabolism / Q000648:ultrastructure; D003593:Cytoplasm / Q000378:metabolism / Q000648:ultrastructure; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D002479:Inclusion Bodies / Q000378:metabolism / Q000648:ultrastructure; D008540:Meiosis; D008854:Microscopy, Electron; D010940:Plant Proteins / Q000378:metabolism; D012337:RNA, Ribosomal, 18S / Q000235:genetics / Q000378:metabolism*; D014197:Trees / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure*
chemical_list: D010940:Plant Proteins; D012337:RNA, Ribosomal, 18S