Figure 2From: Functional significance of nuclear export and mRNA binding of meiotic regulator Spo5 in fission yeast Spo5 localization to the cytoplasm facilitated by the mRNA export pathway does not involve global mRNA export. (A) Spo5–GFP accumulated in the nucleus in temperature-sensitive rae1-167 cells. Cells were incubated at 25°C for 6 h and then transferred to 36°C for 3 h. Cut11-4mRFP was used as a nuclear envelope marker. The Spo5–GFP signal was evident in cells undergoing meiotic prophase I through meiosis II. Scale bar, 5 μm. (B) To block RNA-polymerase II-dependent transcription of mRNAs, we used 1, 10-phenanthroline [49]. Wild-type diploid cells were transferred to MM-N to induce meiosis, and after 3.5 hours (Time 0), 1,10-phenanthroline was added to half of the culture at a final concentration of 500 ng/μL. Microscopic observation of Spo5-GFP was carried out after 2 hours. Scale bar, 5 μm. (C) Quantitative analysis of Spo5-GFP localization in cells treated with 1,10-phenanthroline. The number of cells examined is as follows: 0 h, n = 152; 2 h(-), n = 239; and 2 h(+), n = 207. (D) Cells expressing Spo5–GFP (-LMB) were treated with 100 ng/mL LMB and observed after 1 h (+LMB). Mei2-mCherry served as a positive control since it accumulates in the nucleus upon LMB addition. Scale bar, 5 μm. (E) Pabp–GFP accumulated in the nucleus in rae1-167 cells, whereas it did not do so in spo5∆ cells. Scale bar, 5 μm.Back to article page