Futagami Taiki, Goto Masatoshi
Department of Bioscience and Biotechnology; Faculty of Agriculture; Kyushu University; Hakozaki, Japan.
Commun Integr Biol. 2012 Mar 1;5(2):206-8. doi: 10.4161/cib.18993.
The cell wall integrity (CWI) signal transduction pathway, which has been well-studied in the yeast Saccharomyces cerevisiae, plays an important role in the regulation of cell wall biogenesis. Recently, we characterized the CWI stress sensor orthologs WscA and WscB in the filamentous fungus Aspergillus nidulans. Disruption of the wscA and wscB genes causes a change in the transcriptional levels of agsA and agsB, which encode α-1,3-glucan synthase, resulting in an increase in alkaline soluble cell wall glucan. However, the contribution of these putative sensors to downstream CWI pathway signaling remains unclear because MpkA-RlmA signaling remains active in wscA-wscB double disruptants exposed to cell wall stress associated with exposure to micafungin, a potent inhibitor of β-1,3-glucan synthase. In this addendum, we report the results of further studies involving hypo-osmotic shock as a stressor that suggest WscA and WscB are not essential for MpkA-RlmA signaling. Finally, we describe for the first time other Aspergillus CWI stress sensor candidate Mid2-like protein.
细胞壁完整性（CWI）信号转导途径在酿酒酵母中已得到充分研究，在细胞壁生物合成的调控中发挥着重要作用。最近，我们鉴定了丝状真菌构巢曲霉中CWI应激传感器直系同源物WscA和WscB。wscA和wscB基因的破坏导致编码α-1,3-葡聚糖合酶的agsA和agsB转录水平发生变化，从而导致碱性可溶性细胞壁葡聚糖增加。然而，这些假定的传感器对下游CWI途径信号传导的贡献仍不清楚，因为在暴露于与强力β-1,3-葡聚糖合酶抑制剂米卡芬净相关的细胞壁应激的wscA-wscB双缺失突变体中，MpkA-RlmA信号传导仍然活跃。在本附录中，我们报告了以低渗休克作为应激源的进一步研究结果，这些结果表明WscA和WscB对于MpkA-RlmA信号传导不是必需的。最后，我们首次描述了其他构巢曲霉CWI应激传感器候选物Mid2样蛋白。
