百花山野生植物资源分布情况及主要花卉园林应用评价

百花山自然保护区具有优越的地理位置和良好的气候条件,其中孕育着丰富的植物资源,是北京著名的野生花卉种质资源库.在调查分析其野生植物自然分布情况的同时,对其中的重要花卉的潜在园林利用价值作了简要评价,期望加大对百花山野生花卉资源的开发利用.     

The lifestyle transition of Arthrobotrys oligospora is mediated by microRNA-like RNAs

The lifestyle transition of fungi, defined as switching from taking organic material as nutrients to pathogens, is a fundamental phenomenon in nature. However, the mechanisms of such transition remain largely unknown. Here we show microRNA-like RNAs(milRNAs) play a key role in fungal lifestyle transition for the first time. We identified milRNAs by small RNA sequencing in Arthrobotrys oligospora, a known nematode-trapping fungus. Among them, 7 highly expressed milRNAs were confirmed by northern-blot analysis. Knocking out two milRNAs significantly decreased A. oligospora's ability to switch lifestyles. We further identified that two of these milRNAs were associated with argonaute protein QDE-2 by RNA-immunoprecipitation(RIP) analysis. Three of the predicted target genes of milRNAs were found in immunoprecipitation(IP)products of QDE-2. Disruption of argonaute gene qde-2 also led to serious defects in lifestyle transition. Interestingly, knocking out individual milRNAs or qde-2 lead to diverse responses under different conditions, and qde-2 itself may be targeted by the milRNAs. Collectively, it indicates the lifestyle transition of fungi is mediated by milRNAs through RNA interference(RNAi)machinery, revealing the wide existence of miRNAs in fungi kingdom and providing new insights into understanding the adaptation of fungi from scavengers to predators and the mechanisms underlying fungal infections.