Non-synchronous Degradation of Centrioles during Mating in Physarum polycephalum

Abstract

During mating in Physarum polycephalum, centrioles are lost from both the cytoplasm and the mitotic poles. We studied the timing of the loss of this organelle using immunofluorescence microscopy. Structural loss was complete after the 2nd plasmodial mitosis and occurred in a non-synchronous manner within individually developing cells. After mating, the number of centriolres in some cells increased to 4, indicating that two pairs of centrioles had fused. The number of centrioles did not increase after the 1st plasmodial mitosis, suggesting that although centrioles do exist in some plasmodia during the early stage, they are not replicated and do not function as mitotic poles. Most of the remaining centrioles retained a connection with the cell nucleus.