Abstract:
Zinc (Zn) is a major soil contaminant and high Zn levels can disrupt growth, survival, and reproduction of fungi. Some fungal species evolved Zn tolerance through cell processes mitigating Zn toxicity, though the genes and detailed mechanisms underlying mycorrhizal fungal Zn tolerance remain unexplored. To fill this gap in knowledge, we investigated the gene expression of Zn tolerance in the ectomycorrhizal fungus Suillus luteus. We found that Zn tolerance in this species is mainly a constitutive trait that can also be environmentally dependent. Zinc tolerance in S. luteus is associated with differences in expression of genes involved in metal exclusion and immobilization, as well as recognition and mitigation of metal-induced oxidative stress. Differentially expressed genes were predicted to be involved in transmembrane transport, metal chelation, oxidoreductase activity, and signal transduction. Some of these genes were previously reported as candidates for S. luteus Zn tolerance, while others are reported here for the first time. Our results contribute to understanding the mechanisms of fungal metal tolerance and pave the way for further research on the role of fungal metal tolerance in mycorrhizal associations.
摘要:
锌(Zn)是一种主要的土壤污染物,高锌水平会破坏生长,生存,和真菌的繁殖。一些真菌物种通过减轻锌毒性的细胞过程进化出锌耐受性,尽管菌根真菌锌耐受性的基因和详细机制仍未被探索。为了填补这一知识空白,我们研究了外生菌根真菌藤黄杆菌中锌耐受性的基因表达。我们发现该物种的锌耐受性主要是一种组成性状,也可能与环境有关。黄体葡萄球菌的锌耐受性与金属排斥和固定化基因的表达差异有关,以及识别和缓解金属诱导的氧化应激。预测差异表达基因参与跨膜转运,金属螯合,氧化还原酶活性,和信号转导。这些基因中的一些先前被报道为黄牛锌耐受性的候选基因,而其他人是第一次在这里报道。我们的研究结果有助于理解真菌金属耐受性的机制,并为进一步研究真菌金属耐受性在菌根关联中的作用铺平道路。