Immunolocalisation of <i>Eleutheroschizon duboscqi</i> cytoskeletal proteins.

<p><b>A-B.</b> Actin labelling with a medium intensity in a trophozoite (PFA fixation). CLSM, IFA (A) and CLSM in a combination with transmission LM, IFA/DAPI (B). B represents a single median optical section. <b>C.</b> Actin labelling in a macrogamont treated with 30 μM JAS for 7 hours (PFA fixation). Note the increased accumulation of parasite actin (FITC) organised in longitudinal bands exhibiting strong fluorescence and strong F-actin (TRITC) labelling with a diffuse character. CLSM, IFA/phalloidin-TRITC. <b>D.</b> A gamont exhibiting a more diffuse actin (FITC) labelling of medium intensity after treatment with 10 μM cytochalasin D for 9 hours (PFA fixation). The F-actin (TRITC) labelling of the parasite did not change significantly. CLSM, IFA/phalloidin-TRITC. <b>E.</b> Very strong myosin (TRITC) labelling restricted to the PS and host tissue (PFA fixation). CLSM, IFA/DAPI. <b>F.</b> Strong spectrin (FITC) labelling of the PS in a macrogamont (PFA fixation). CLSM, IFA/DAPI. Single median optical section. <b>G.</b> Labelling of α-tubulin (FITC) of strong intensity in a young microgamont (PFA fixation). CLSM, IFA/DAPI. <b>H-I.</b> A trophozoite (fixed in ice-cold methanol) exhibiting a labelling of medium intensity for α-tubulin (FITC) and very strong intensity for myosin (TRITC). CLSM, IFA/DAPI. <b>J.</b> Labelling of α-tubulin (FITC) and myosin (TRITC) in an early trophozoite treated for 7 hours with 10 μM oryzalin (fixed in ice-cold methanol). The fluorescence signals for both antibodies did not change significantly. CLSM, IFA. <b>K-L.</b> Localisation of α-tubulin (FITC) and myosin (TRITC) in an individual (probably a young microgamont) treated with 30 μM oryzalin for 3 hours (fixed in ice-cold methanol). The fluorescence signal for tubulin became very weak, while it remained very strong for myosin. CLSM, IFA/DAPI. <b>M.</b> Co-localisation of α-tubulin (FITC) and F-actin (TRITC) in a macrogamont treated for 7 hours with 10 μM oryzalin (PFA fixation). CLSM, IFA/phalloidin-TRITC. <b>N-O.</b> Labelling of α-tubulin (FITC) and F-actin (TRITC) in a maturing trophozoite treated for 3 hours with 30 μM oryzalin (PFA fixation). CLSM, IFA/phalloidin-TRITC/DAPI. In both the preparations (M-O), there was almost no fluorescence signal for α-tubulin, while the F-actin labelled with a strong intensity. <i>arrow</i>—tail of the PS, <i>asterisk</i>—parasite attachment site, <i>black arrowhead</i>—PS, <i>h—</i>host tissue, <i>n—</i>parasite nucleus, <i>white arrowhead</i>—parasite pellicle.