ABSTRACT
RNA interference inhibitors were initially discovered in plant viruses, representing a unique mechanism employed by these viruses to counteract host RNA interference. This mechanism has found extensive applications in plant disease resistance breeding and other fields; however, the impact of such interference inhibitors on insect cell RNA interference remains largely unknown. In this study, we screened three distinct interference inhibitors from plant and mammal viruses that act through different mechanisms and systematically investigated their effects on the insect cell cycle and baculovirus infection period at various time intervals. Our findings demonstrated that the viral suppressors of RNA silencing (VSRs) derived from plant and mammal viruses significantly attenuated the RNA interference effect in insect cells, as evidenced by reduced apoptosis rates, altered gene regulation patterns in cells, enhanced expression of exogenous proteins, and improved production efficiency of recombinant virus progeny. Further investigations revealed that the early expression of VSRs yielded superior results compared with late expression during RNA interference processes. Additionally, our results indicated that dsRNA-binding inhibition exhibited more pronounced effects than other modes of action employed by these interference inhibitors. The outcomes presented herein provide novel insights into enhancing defense mechanisms within insect cells using plant and mammal single-stranded RNA virus-derived interference inhibitors and have potential implications for expanding the scope of transformation within insect cell expression systems.
ABSTRACT
BACKGROUND: The soil fungal community plays an important role in global carbon cycling and shows obvious seasonal variations, however, drivers, particularly stochastic drivers, of the seasonal variation in the fungal community have never been addressed in sufficient detail. METHODS: We investigated the soil fungal community variation between summer growing (SG) and winter fallow (WF) stage, through high throughput sequencing of internal transcribed spacer (ITS) amplicons. Subsequently, we assessed the contribution of different ecological processes to community assembly using null-model-based statistical framework. RESULTS: The results showed that the fungal community diversity decreased significantly after tobacco cropping in the SG stage and the composition showed a clear turnover between the WF and SG stages. The variation in community composition was largely attributable to the presence of a small portion of Dothideomycetes in the WF stage that dominated the soil fungal community in the SG stage. The organic matter, temperature, and water content were the main deterministic factors that regulated the fungal community; these factors explained 34.02% of the fungal community variation. Together with the result that the fungal community was mainly assembled by the dispersal process, our results suggested that the stochastic factors played important roles in driving the seasonal variation of fungal community. The dispersal limitation dominated the fungal community assembly during the WF stage when homogenizing dispersal was the main assembly process of the fungal community in the SG stage. Thus, we proposed that the dispersal processes are important drivers for seasonal variation of fungal community in tobacco planted soil.
