Fig. 8. Localisation of cdc2-YFP during mating, karyogamy and meiosis. (A) Cartoon summarizing the localisation of chromosomes, centromeres (), telomeres () and SPB () during mating, karyogamy and meiotic prophase in S. pombe as described (Chikashige et al., 1994; Chikashige et al., 1997). (B) A cdc2-YFP-expressing strain (AD185) and a cdc2⁺ strain (PN745) were crossed on nitrogen-depleted medium and observed by LFM. Conjugating cells (a-b). Both nuclei become fluorescent (b). During karyogamy, cdc2-YFP is enriched in bright dots (c-f, arrowheads). In the horse-tail nucleus, cdc2-YFP is concentrated into 1-3 bright dots (g-k). Nucleus movement stops and meiosis I starts (l-s). We followed cdc2-YFP fluorescence in the same diploid cell for 70 minutes from meiotic prophase (i) to metaphase of the first meiotic division (s). Meiosis I (s-u). Meiosis II (v-x).