RNAseq analysis of mutants in coding and non-coding transcription of phosphate genes in the yeast Saccharomyces cerevisiae.

This study addresses the effect of mutations related to sense and antisense transcription of Saccharomyces cerevisiae phosphate genes using strand-specific RNAseq. Replacement of the transcriptional terminator of PHO84 by that of CYC1 resulted, unexpectedly, in an increased antisense transcription and a strongly reduced sense transcription of PHO84. Also RNA levels of SPL2 were strongly reduced. Deletion of the PHO84 coding region did not markedly affect the expression of SPL2, suggesting that antisense transcription of PHO84 and not the Pho84 transporter affects the expression of SPL2. Deletion of the two putative binding sites for the transcriptional regulator Ume6 in the SPL2 promoter resulted in a slightly increased level of SPL2 RNA, whereas deletion of the UME6 gene resulted in a decreased level of SPL2 and PHO84 RNA. These results suggests that Ume6 is involved in the regulation of SPL2 by a mechanism different from a simple binding to the putative Ume6 binding sites. Samples were analyzed in two series. In the first series three independent cultures of BY4741, three independent cultures of BY4741ΔP and three independent cultures of BY4741Tpho84-Tcyc1 were used. In the second series two independent cultures of BY4741, three independent cultures of BY4741ΔU, three independent culture of ume6Δ, two independent culture of pho4Δ and two independent culture of pho84Δ were used.