Author:
López-Velázquez Gabriel,Hernández Roberto,López-Villaseñor Imelda,Reyes-Vivas Horacio,Segura-Valdez María de L.,Jiménez-García Luis F.
Abstract
The nucleolus is the main site for synthesis and processing of ribosomal RNA in eukaryotes. In mammals, plants, and yeast the nucleolus has been extensively characterized by electron microscopy, but in the majority of the unicellular eukaryotes no such studies have been performed. Here we used ultrastructural cytochemical and immunocytochemical techniques as well as three-dimensional reconstruction to analyze the nucleolus ofTrypanosoma cruzi, which is an early divergent eukaryote of medical importance. InT. cruziepimastigotes the nucleolus is a spherical intranuclear ribonucleoprotein organelle localized in a relatively central position within the nucleus. Dense fibrillar and granular components but not fibrillar centers were observed. In addition, nuclear bodies resembling Cajal bodies were observed associated to the nucleolus in the surrounding nucleoplasm. Our results provide additional morphological data to better understand the synthesis and processing of the ribosomal RNA in kinetoplastids.
Publisher
Cambridge University Press (CUP)
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