Fig. 5. Cyclin B is stabilized on the meiotic spindle in cort, fzy and Cks30A. (A-B',D-H') Tubulin is red, DNA is green and cyclin B is blue. Cyclin B is shown by itself in grayscale in right hand panels (labeled with '). (A) In wild type, cyclin B accumulates on the spindle mid-zone in metaphase of meiosis II. (B) Arrested meiosis II spindle from cort^QW55/cort^RH65 at 29°C, with high levels of cyclin B associated with the mid-zone of the spindle. (C,C') Co-labeling of a metaphase II spindle from cort^QW55/cort^RH65 with antibodies to Sub (C) and cyclin B (C') reveals colocalization at the spindle mid-zone. (D) Meiosis II spindle from fzy⁶/fzy⁷, showing the accumulation of cyclin B along the length of the spindle. (E) Metaphase-arrested meiotic spindle from cort^QW55,fzy⁶/cort^RH65,fzy⁷ with a high level of cyclin B at the spindle mid-zone. (F) Meiotic spindle from Cks30A^KO/Cks30A^KO, with elevated levels of cyclin B on the spindle mid-zone and along the spindle. (G,H) Mitotic spindles in yw (G) and fzy⁶/fzy⁷ (H). In wild type, cyclin B associates with the spindle mid-zone late in metaphase, before disappearing from the spindle in anaphase. In fzy, cyclin B accumulates along the length of the arrested mitotic spindle. Scale bars: 5 µm in A for A-B',D-H';. 2 µm in C for C,C'.