Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-4-1
pubmed:abstractText
An important aspect of the biology of Naegleria sp. is the differentiation processes that occur during encystation and excystation. We studied these using both fluorescence and transmission electron microscopy techniques. In the initial stages of encystation, the cisternae of the endoplasmic reticulum became densely filled with a fibrillar material. Vesicles with a similar content that appeared to be derived from the cisternae were also observed in close contact with the plasma membrane. As encystation progressed, the fibrillar material became localized on the surface of the amoeba. An irregular compaction was observed in some areas of the cyst wall, which contained thin extensions of the cyst wall fibrillar material. Completely formed cysts had two to three ostioles, each sealed by an operculum. The operculum contained two areas in which a differential compaction of the fibrillar structure was observed. When excystation was induced, small dense granules (DGs), which were in close contact with fibrillar material were observed in the cyst cytoplasm and in the peritrophic space. During excystation, the more compact component of the operculum moves to enable the pseudopod of the emerging trophozoite to penetrate the ostiole. Vacuoles containing a fibrillar material, probably derived from the cyst wall, were observed in the cytoplasm of the pseudopodia. Our results provide a platform for further studies using biochemical markers to investigate the origin of the cyst wall as well as the role of DGs during excystation in Naegleria.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
1550-7408
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
66-72
pubmed:meshHeading
pubmed:articleTitle
Ultrastructural study of the encystation and excystation processes in Naegleria sp.
pubmed:affiliation
Department of Experimental Pathology, Center for Research and Advanced Studies, Avenue IPN 2508, Zacatenco, Mexico City 07360, Mexico. bchavez@cinvestav.mx
pubmed:publicationType
Journal Article