The regulation of nuclear migration and division during pseudo-mycelium outgrowth in the dimorphic yeast Candida albicans.

The relationships of the first nuclear division during pseudo-mycelial outgrowth in the infectious yeast Candida albicans to pseudo-mycelial length and DNA replication have been investigated. Evidence is presented that the first nuclear division does not occur until the pseudo-mycelium grows to a minimum length equal to or greater than the diameter of the mother cell and until the cells pass through a minimum time period of approx. 150 min which probably reflects the time necessary to complete nuclear DNA replication. Evidence is also presented that pseudo-mycelial outgrowth and nuclear migration occur independently of DNA replication, and that nuclear migration is probably regulated by the length rather than by the volume of the growing pseudomycelium. Similarities to the requirements for nuclear division during budding in Saccharomyces are discussed, and a model for nuclear migration is proposed.