Figure 1.

Transcription of the spo13⁺ and spo2⁺ genes. Northern analysis of spo13⁺ and spo2⁺ transcripts in pat1-driven meiosis. Synchronous meiosis was initiated in diploid strains homozygous for pat1-114 (JZ670) (A) and pat1-114 mei4Δ (AB4) (B). At hourly intervals, total RNA was prepared and analyzed by Northern blot hybridization. Meiotic nuclear division was monitored by counting the number of nuclei per cell. □, mononucleate; ○, binucleate; ▴, tri- or tetranucleate cells. (C) Effect of ectopic expression of mei4⁺ on spo13⁺ and spo2⁺ transcription. Wild-type cells (TN8) carrying either pREP1 or pREP1(mei4) were incubated in MM+N at 30°C for 13, 15, and 17 h. The approximate quantity of RNA was checked by staining gels with ethidium bromide. A Mei4-dependent gene spo6⁺ was included as a positive control.