Fine structure of shiitake, Lentinus edodes. VI. Cytoplasmic microtubules in relation to nuclear movement

Abstract

In the course of electron microscopic observations on basidiosporogenesis of L. edodes (Berk.) Sing., the cytoplasmic microtubules, which are about 24 nm in diameter and associate closely with the postmeiotic nuclei, were observed to be common during movement of nuclei from a basidium into the respective basidiospores through sterigmata. These microtubules orient striately from the spindle-pole body (SPB), situated at the leading portion of a migrating nucleus, into the cytoplasm of a nearly mature basidiospore and appear to precede the migrating nucleus. The association of microtubules radiating from the SPB with the interior of a migrating nucleus was particularly indicated as being a characteristic event observed during nuclear movement of L. edodes. After completion of nuclear movement, these microtubules disappear completely. The microtubules associated with SPB may play an essential role in nuclear movement from the basidium to the basidiospore.