Identification of nucleoli in the early branching protist Giardia duodenalis.
Giardia duodenalis has been described as 'anucleolated'. In this work we analysed the subcellular distribution of several nucleolar markers in Giardia nuclei using silver and immunostaining techniques for electron and confocal laser microscopy as well as expression of epitope-tagged proteins in transgenic trophozoites. We identified anteronuclear fibrogranular structures corresponding to nucleolar organising regions with recruited ribonucleoprotein complexes, rRNA and epitope-tagged fibrillarin and rRNA-pseudouridine synthase (CBF5). Recombinant fibrillarin and CBF5 were targeted to this subcompartment. This study demonstrates the presence of nucleoli in G. duodenalis and provides a model to analyse minimal requirements for nucleolar assembly and maintenance in eukaryotic cells.
Jiménez-García
Luis Felipe
LF
Departamento de Biología Celular, Facultad de Ciencias-Universidad Nacional Autónoma de México, Mexico City, Mexico.
Zavala
Guadalupe
G
Chávez-Munguía
Bibiana
B
Ramos-Godínez
María del Pilar
Mdel P
López-Velázquez
Gabriel
G
Segura-Valdez
María de Lourdes
Mde L
Montañez
Cecilia
C
Hehl
Adrian B
AB
Argüello-García
Raúl
R
Ortega-Pierres
Guadalupe
G
D000818:Animals; D002466:Cell Nucleolus / Q000378:metabolism / Q000648:ultrastructure*; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics*; D019143:Evolution, Molecular; D005872:Giardia / Q000378:metabolism / Q000648:ultrastructure*; D006801:Humans; D018613:Microscopy, Confocal; D008854:Microscopy, Electron; D009697:Nucleolus Organizer Region / Q000378:metabolism / Q000648:ultrastructure*; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D012335:RNA, Ribosomal / Q000235:genetics / Q000378:metabolism
D002868:Chromosomal Proteins, Non-Histone; D015800:Protozoan Proteins; D012335:RNA, Ribosomal; C047458:fibrillarin