Nuclear Elimination During Cyst Formation in Woronina Pythii (Plasmodiophoromycetes)

ABSTRACT

Nuclear elimination in Woronina pythii was a complex event that occurred in a series of steps during the formation of cysts. Approximately 16% of the nuclei within each Plasmodium migrated, aggregated, fused, and degenerated as the parasite thallus matured. During each step of the elimination-degeneration process, the movements and behavior of nuclei were coordinated synchronously. Each nucleus had at least three nuclear projections. Nuclear projections might function as internuclear spacing devices which establish and maintain a specific 3-dimensional distance between contiguous nuclei within each multinucleate Plasmodium. The elimination of nuclei probably aids in establishing a proper nucleoplasmiccytoplasmic ratio prior to cyst formation.

Key Words:

• Woronina
• nuclear projections
• nuclear degeneration