iBB-Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001, Lisbon, Portugal.
Sci Rep. 2018 Sep 20;8(1):14122. doi: 10.1038/s41598-018-32266-9.
The non-conventional yeast species Zygosaccharomyces bailii is remarkably tolerant to acetic acid, a highly important microbial inhibitory compound in Food Industry and Biotechnology. ZbHaa1 is the functional homologue of S. cerevisiae Haa1 and a bifunctional transcription factor able to modulate Z. bailii adaptive response to acetic acid and copper stress. In this study, RNA-Seq was used to investigate genomic transcription changes in Z. bailii during early response to sublethal concentrations of acetic acid (140 mM, pH 4.0) or copper (0.08 mM) and uncover the regulatory network activated by these stresses under ZbHaa1 control. Differentially expressed genes in response to acetic acid exposure (297) are mainly related with the tricarboxylic acid cycle, protein folding and stabilization and modulation of plasma membrane composition and cell wall architecture, 17 of which, directly or indirectly, ZbHaa1-dependent. Copper stress induced the differential expression of 190 genes mainly involved in the response to oxidative stress, 15 ZbHaa1-dependent. This study provides valuable mechanistic insights regarding Z. bailii adaptation to acetic acid or copper stress, as well as useful information on transcription regulatory networks in pre-whole genome duplication (WGD) (Z. bailii) and post-WGD (S. cerevisiae) yeast species, contributing to the understanding of transcriptional networks' evolution in yeasts.
非传统酵母物种毕赤酵母对乙酸具有显著的耐受性，乙酸是食品工业和生物技术中一种非常重要的微生物抑制化合物。ZbHaa1 是酿酒酵母 Haa1 的功能同源物，是一种具有双重功能的转录因子，能够调节毕赤酵母对乙酸和铜胁迫的适应性反应。在这项研究中，使用 RNA-Seq 技术研究了毕赤酵母在早期对低浓度乙酸（140mM，pH4.0）或铜（0.08mM）的反应中基因组转录变化，并揭示了在 ZbHaa1 控制下这些应激激活的调控网络。对乙酸暴露的差异表达基因（297 个）主要与三羧酸循环、蛋白质折叠和稳定以及质膜组成和细胞壁结构的调节有关，其中 17 个基因直接或间接受 ZbHaa1 调控。铜胁迫诱导了 190 个差异表达基因的表达，主要涉及对氧化应激的反应，其中 15 个基因受 ZbHaa1 调控。这项研究提供了关于毕赤酵母适应乙酸或铜胁迫的有价值的机制见解，以及关于在全基因组复制（Z. bailii）和后全基因组复制（S. cerevisiae）酵母物种中转录调控网络的有用信息，有助于理解酵母中转录网络的进化。
