New details on the fine structure of the rhoptry of Toxoplasma gondii.

摘要: Rhoptries are organelles that have important, complex roles in Apicomplexa biology. During Toxoplasma gondii infection, these take part several essential and processes include host cell entry parasite development. Using different electron microscopy techniques, we characterized the fine morphology of rhoptries two most important life stages T. gondii: tachyzoite bradyzoite forms. The observed had delimited regions by a dark electron-dense neck, an amorphous less bulb, region intermediate density, which connects bulb to neck. Metal replicas frozen-fractured tachyzoites showed intramembranous particles densities sizes on fractured faces rhoptry membranes. Both bradyzoites, were arranged distinctive parallel arrays decorated organelles. Tubulo-vesicular subcompartments free within lumen freeze-fractured replicas. Cryo-fixed, deep-etched samples pore-like structures localized portion. No obvious evidence was found possible connection between micronemes.