Disruption of antisense transcription allows <i>spo6⁺</i> sense transcription in vegetative cells.

<p>(A) Illustration of <i>spo6</i> antisense disruption strains. The arrow above <i>spo6⁺</i> represents the sense RNA. The arrow below <i>spo6⁺</i> represents the antisense RNA, which is the long 3′UTR of SPBC1178.05c (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029917#pone-0029917-g001" target="_blank">Figure 1B</a>). Two antisense knockout strains were constructed. KO1: insertion of the U1 terminator into SPBC1778.05c in the same transcription direction as <i>SPBC1778.05c</i>. KO2: insertion of the <i>ura4⁺</i> cassette (promoter-<i>ura4⁺</i>-terminator) between <i>spo6⁺</i> and SPBC1778.05c in the same transcription direction as s<i>po6⁺</i>. (B) Radioactive PCR detection of <i>spo6⁺</i> sense and antisense RNAs. <i>adh1⁺</i> is included as internal loading control, and <i>adh1⁺</i> (-RT) indicates no genomic DNA contamination. Antisense RNAs decrease and sense RNAs appear in both antisense KO strains. Fkh2 has minimal effect on <i>spo6</i> sense and antisense transcription. The relative sense and antisense RNA level were quantified and normalized to <i>adh1⁺</i> to show the fold change. The <i>adh1</i> transcript drops by about 30% in meiosis, and this was taken into account in the normalization. Two or more isolates for each strain were assayed. This figure shows the representative result.