The cytoskeleton of pathogenic protists

The cytoskeleton is a key component of eukaryotic cells, including protists. It is composed of microtubules, microfilaments, and intermediate filaments. Here, we review the available information on the cytoskeleton of several relevant pathogenic protists, including Trypanosomatidae, Apicomplexa, Trichomonadidae, Giardia intestinalis, and Entamoeba histolytica. In protists, the first two components, made of tubulins and actin, predominate. Usually, they associate with each other and with other components to form complex structures. Emphasis is given to the following structures: flagellum, flagellar-cell body adhesion zone, paraflagellar rod, sub-pellicular microtubules, cytostome, conoid, adhesive disc, funis, median body, costa, axostyle, parabasal filaments, and clockwise filaments. On the other hand, filamentous structures made of not yet completely characterized proteins form structures such as the costa. Each structure is analyzed using morphological information obtained through modern microscopy techniques and biochemical data.