Protoplasmic streaming during the cell cycle of Physarum polycephalum

It has been reported that protoplasmic streaming stops during the synchronous mitosis exhibited by growing plasmodia of P. polycephalum. Our data reveal that at no time during the mitotic cycle did streaming stop. However, during a 3-5 min period at anaphase the percent of each oscillation period accounted for by an outward flow was precisely equal in duration to the corresponding inward flow. At all other periods the duration of outward flow exceeded that of inward flow. Plasmodial migration or locomotion was briefly arrested at telophase, although shuttle streaming persisted.