報告1：Moving from descriptive to predictive biology: Rational rewiring of the cell factory Aspergillus niger
報 告 人：Vera Meyer 德國柏林工業大學教授
報告題目：Moving from descriptive to predictive biology: Rational rewiring of the cell factory Aspergillus niger
報告摘要：Fungal biotechnology is currently undergoing a renaissance with important implications for its role as platform technology for the sustainable production of products, goods and drugs. Allied to this are the recent advances in fungal Systems and Synthetic Biology which can be seen as two complementary approaches to investigate the complexity of biological systems including fungi. Whereas Systems Biology analyzes cellular systems in an iterative cycle of high-throughput generation of omics data and modeling, Synthetic Biology takes a constructive approach to reengineer biological networks and to design novel biological parts and circuits with non-natural function. Both disciplines – systems analysis and design – ideally complement each other and, not surprisingly, aim to discover the design principles of (fungal) Life.
Our goal is to understand and rationally rewire the industrial cell factory Aspergillus niger. On the one hand, we generate and evaluate different omics data types for A. niger and use these Big Data to predict gene function as well as gene regulatory networks. On the other hand, we engineer titratable and tightly regulated conditional mono- and polycistronic gene switches and target them to specific genomic loci. By combining these two activities, we not only successfully improve A. niger as producer for proteins, new natural products or even new-to-nature compounds, we are also entering a new era in Aspergillus niger biology: we are moving from descriptive to predictive biology.
報告2：New avenues towards optimal morphology in the industrial fungus Aspergillus niger
報 告 人：Timothy Charlie Cairns德國柏林工業大學博士
報告題目：New avenues towards optimal morphology in the industrial fungus Aspergillus niger
報告摘要：In filamentous fungi, growth and protein secretion occurs predominantly at the tip of long, thread like cells termed hyphae. This requires coordinated regulation of multiple processes, including vesicle trafficking, exocytosis, and endocytosis, which are facilitated by a complex cytoskeletal apparatus. In this study, functional analyses of the small GTPase ArfA from Aspergillus niger demonstrate that this protein functionally complements the Saccharomyces cerevisiae ARF1/2, and that this protein is essential for A. niger. Loss-of-function and gain-of-function analyses demonstrate that titration of arfA expression impacts hyphal growth rate, hyphal tip morphology, and protein secretion. Moreover, localization of the endocytic machinery, visualized via fluorescent tagging of the actin ring, was found to be abnormal in ArfA under- and overexpressed conditions. Finally, we provide evidence that the major secreted protein GlaA localizes at septal junctions, indicating that secretion in A. niger may occur at these loci, and that this process is likely impacted by arfA expression levels. Taken together, our results demonstrate that ArfA fulfils multiple functions in the secretory pathway of A. niger.