Global S&T Development Trend Analysis Platform of Resources and Environment
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Reverse genetics has been an indispensable tool to gain insights into viral pathogenesis and vaccine development. The genomes of large RNA viruses, such as those from coronaviruses, are cumbersome to clone and manipulate inEscherichia coliowing to the size and occasional instability of the genome(1-3). Therefore, an alternative rapid and robust reverse-genetics platform for RNA viruses would benefit the research community. Here we show the full functionality of a yeast-based synthetic genomics platform to genetically reconstruct diverse RNA viruses, including members of theCoronaviridae,FlaviviridaeandPneumoviridaefamilies. Viral subgenomic fragments were generated using viral isolates, cloned viral DNA, clinical samples or synthetic DNA, and these fragments were then reassembled in one step inSaccharomyces cerevisiaeusing transformation-associated recombination cloning to maintain the genome as a yeast artificial chromosome. T7 RNA polymerase was then used to generate infectious RNA to rescue viable virus. Using this platform, we were able to engineer and generate chemically synthesized clones of the virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)(4), which has caused the recent pandemic of coronavirus disease (COVID-19), in only a week after receipt of the synthetic DNA fragments. The technical advance that we describe here facilitates rapid responses to emerging viruses as it enables the real-time generation and functional characterization of evolving RNA virus variants during an outbreak.
A yeast-based synthetic genomics platform is used to reconstruct and characterize large RNA viruses from synthetic DNA fragments
V gamma 6(+) V delta 1(+) gamma delta T cells control tolerance to cold by activating adipocyte IL-17RC and promoting sympathetic innervation of thermogenic adipose tissue in mice.
The sympathetic nervous system innervates peripheral organs to regulate their function and maintain homeostasis, whereas target cells also produce neurotrophic factors to promote sympathetic innervation(1,2). The molecular basis of this bi-directional communication remains to be fully determined. Here we use thermogenic adipose tissue from mice as a model system to show that T cells, specifically gamma delta T cells, have a crucial role in promoting sympathetic innervation, at least in part by driving the expression of TGF beta 1 in parenchymal cells via the IL-17 receptor C (IL-17RC). Ablation of IL-17RC specifically in adipose tissue reduces expression of TGF beta 1 in adipocytes, impairs local sympathetic innervation and causes obesity and other metabolic phenotypes that are consistent with defective thermogenesis
An Amendment to this paper has been published and can be accessed via a link at the top of the paper.