Defects before anaphase onset and environmental stresses can delay ring disassembly. (A–C) DNA (blue), tubulin (green), and AIR-2 (red) in control and error-induced spindles. AIR-2 stays ring associated after a variety of perturbations, and ring disassembly is delayed both in spindles with (B) and without (A) lagging chromosomes. (C) zen-4(RNAi) does not delay ring disassembly in MI but can cause AIR-2 to remain in rings in MII when there is double the chromosome number. (D) Quantification of mid anaphase spindles with AIR-2 in rings for all conditions tested and includes MI and MII spindles for all conditions except depletion of zen-4, cyk-4, and ani-1. (E) DNA (blue), tubulin (green, column 1), AIR-2 (red), and MPM-2 (green, column 4) in control and error-induced spindles. MPM-2 marks the ring structures, illustrating that additional ring proteins are stabilized when AIR-2 persists in rings under error conditions. Bars, 2.5 µm.