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Veterinary parasitology2001; 95(2-4); 263-271; doi: 10.1016/s0304-4017(00)00392-7

Ultrastructure of schizonts and merozoites of Sarcocystis neurona.

Abstract: The ultrastructure of Sarcocystis neurona schizonts and merozoites was studied in specimens derived from cell culture and from the brains of infected mice. Schizonts and merozoites were located in the host cell cytoplasm without a parasitophorous vacuole at any stage of development. Merozoites divided by endopolygeny. Fully formed merozoites had a pellicle, numerous polysomes and ribosomes, smooth and rough endoplasmic reticulum, 22 subpellicular microtubules, 9-16 dense granules, 25-75 micronemes, a plastid, a Golgi complex, 1-3 mitochondria, a conoid, 2 apical rings, 2 polar rings, 0-6 lipid bodies, a nucleus and nucleolus, but no rhoptries. Most micronemes were located anterior to the nucleus including 1-6 micronemes in the conoid. Merozoites were either slender (7.3 microm x 1.7 microm) or stumpy (7.7 microm x 3.1 microm). Dense granules appeared to arise from the maturation face of the Golgi complex. The ultrastructure of in vitro derived schizonts and merozoites were similar to in vivo derived organisms.
Publication Date: 2001-02-27 PubMed ID: 11223206DOI: 10.1016/s0304-4017(00)00392-7Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't
  • Research Support
  • U.S. Gov't
  • Non-P.H.S.

Summary

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This study explores the ultrastructure of two developmental stages (schizonts and merozoites) of the Sarcocystis neurona, a parasitic organism, using samples from lab cultures and brains of infected mice. The study reveals the parasites’ structures, their location inside the host cell, and their division process, among other features.

Overview of the Study and its Objectives

  • The research focuses on surveying and detailing the ultrastructure of schizonts and merozoites, which are two developmental phases of Sarcocystis neurona, a protozoan parasite that can infect various host types, including mammals.
  • By studying samples from both a laboratory culture and the brains of infected mice, the scholars offer a comprehensive overview of these parasite stages in different environments.
  • The primary goal of this study is to provide more context and knowledge about this parasite’s shape, structural details, and behavior in host cells, which can act as key insights for future research and potential treatments.

Ultrastructure of Schizonts and Merozoites

  • The article conveys that schizonts and merozoites of Sarcocystis neurona are situated in the host cell cytoplasm sans a parasitophorous vacuole during all development stages.
  • The division of the merozoites takes place by endopolygeny, a process where one mother cell divides into multiple daughter cells.
  • The fully formed merozoites possess various elements, such as a pellicle, polysomes, ribosomes, endoplasmic reticulum, several microtubules, dense granules, and micronemes. Besides, they contain a Golgi complex, mitochondria, a nucleus with a nucleolus, and lipid bodies, among others.

Sizes and Structures

  • The scholars classify merozoites into two groups based on their shape and size: slender (approximately 7.3 microm x 1.7 microm) or stumpy (roughly 7.7 microm x 3.1 microm).
  • The dense granules in the cell structure, which contain substances used by the parasite to infect host cells and survive, seem to come from the maturation aspect of the Golgi complex, an essential cell organelle in protein processing and transport.

Comparison of In Vivo and In Vitro Samples

  • Notably, the research identifies that the ultrastructure of both in vitro (from the lab culture) and in vivo (from mice brains) derived schizonts and merozoites are alike, indicating that the development and behavior of these parasites are consistent regardless of the environment.

Cite This Article

APA
Speer CA, Dubey JP. (2001). Ultrastructure of schizonts and merozoites of Sarcocystis neurona. Vet Parasitol, 95(2-4), 263-271. https://doi.org/10.1016/s0304-4017(00)00392-7

Publication

ISSN: 0304-4017
NlmUniqueID: 7602745
Country: Netherlands
Language: English
Volume: 95
Issue: 2-4
Pages: 263-271

Researcher Affiliations

Speer, C A
  • Department of Veterinary Molecular Biology, Montana State University, Bozeman 59717-3610, USA.
Dubey, J P

    MeSH Terms

    • Animals
    • Brain / parasitology
    • Cattle
    • Coturnix
    • Horses
    • Interferon-gamma / physiology
    • Mice
    • Mice, Knockout
    • Microscopy, Electron
    • Rodent Diseases / parasitology
    • Sarcocystis / ultrastructure
    • Sarcocystosis / parasitology
    • Sarcocystosis / veterinary

    Citations

    This article has been cited 10 times.
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