Segregation of a microsporidian parasite during host cell mitosis

We investigated the segregation of an intracellular microsporidian parasite during host cell division. A time-course experiment was carried out to exa mine the distribution of parasites relative to host chromosomal DNA via lig ht and electron microscopy. Fluorescent light microscopy and EM studies sho wed that the parasite lay in the perinuclear zone of the host cell during i nterphase and segregated to daughter cells at mitosis. At metaphase, the pa rasite was frequently closely associated with host microtubules and mitocho ndria. Electron-dense bridges were observed between the parasites and the h ost microtubules and also between host mitochondria and microtubules. The s tudy suggests that both the parasite and the host sell organelles segregate in association with spindle microtubules.