Meiosis inSchizophyllum commune: premeiotic DNA replication and meiotic synchrony induced with hydroxyurea

Abstract
SUMMARY: Hydroxyurea (HU) effectively inhibits meiosis inSchizophyllum. The predominant cytological stage in inhibited fruit bodies is fusion. The inhibition is reversible and makes possible synchronization of a naturally nonsynchronous system. Microphotometric determinations of the DNA content in prefusion nuclei treated with HU suggest that premeiotic DNA replication occurs in prefusion nuclei. Synaptinemal complexes are not completed in HU-treated nuclei, suggesting that this event is dependent on premeiotic DNA replication.