F-actin relocalizes from the contractile ring to the poles upon inhibition of PLC or MLCK. Confocal images of dividing crane-fly spermatocytes stained for (A-E) F-actin and (A'-E') tyrosinated tubulin. (A, A') Untreated control cell. In untreated cells, F-actin was concentrated in the contractile ring (A) and tubulin in the spindle (A'). (B, B') Cell treated with U73122. (C, C') Cell treated with ET-18-OCH3. (D, D') Cell treated with ML-7. Cells treated with these inhibitors had reduced contractile ring F-actin and accumulation of F-actin at the poles (B-D). (E, E') Cell treated with NEM. Note small band of F-actin at the equator, as well as reduced F-actin density throughout the rest of the cell. Also note loss of astral microtubules (E'). Bar, 10 μm.