Expression of the short transcript is regulated by an intragenic control element but not the TATA element of ASP3. (A) Reporter assays of the wild-type strain with an empty vector (pLG669Z-UASΔ) or a plasmid containing the ASP3(306-657) coding region upstream of the LacZ reporter gene (pLG669Z-PncASP3) were conducted under ammonium-containing or nitrogen starvation conditions. The β-galactosidase activities shown are means of three independent measurements. (B) Total RNAs were extracted from wild-type and asp3Δ mutant strains containing an empty vector (Vec), wild-type (ASP3), TATA box-deleted (tataΔ), or intragenic control element-deleted (iceΔ) expressing plasmid (pRS316 backbone) in ammonium-containing medium and under nitrogen starvation. The ASP3 and ncASP3 signals determined by Northern blotting were normalized to ACT1 and are displayed below the blots.
