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Shaw, W. M.

Publications and source records attributed to Shaw, W. M..

2 recordsLinked to original sources

Engineering a model cell for rational tuning of GPCR signaling

G protein-coupled receptor (GPCR) signaling is the primary method eukaryotes use to respond to specific cues in their environment. However, the relationship between stimulus and response for each GPCR is difficult to predict due to diversity in natural signal transduction architecture and expression. Using genome engineering in yeast, we here constructed an insulated, modular GPCR signal transduction system to study how the response to stimuli can be predictably tuned using synthetic tools. We delineated the contributions of a minimal set of key components via computational and experimental refactoring, identifying simple design principles for rationally tuning the dose-response. Using four different receptors, we demonstrate how this enables cells and consortia to be engineered to respond to desired concentrations of peptides, metabolites and hormones relevant to human health. This work enables rational tuning of cell sensing, while providing a framework to guide reprogramming of GPCR-based signaling in more complex systems.

synthetic biology

Convergent evolution of psilocybin biosynthesis by psychedelic mushrooms

Psilocybin is a psychoactive compound with clinical applications produced by dozens of mushroom species1. There has been a longstanding interest in psilocybin research with regard to treatment for addiction2, depression3, and end-of-life suffering4. However, until recently very little was known about psilocybin biosynthesis and its ecological role. Here we confirm and refine recent findings5 about the genes underpinning psilocybin biosynthesis, discover that there is more than one psilocybin biosynthesis cluster in mushrooms, and we provide the first data directly addressing psilocybins ecological role. By analysing independent genome assemblies for the hallucinogenic mushrooms Psilocybe cyanescens and Pluteus salicinus we recapture the recently discovered psilocybin biosynthesis cluster5,6 and show that a transcription factor previously implicated in its regulation is actually not part of the cluster. Further, we show that the mushroom Inocybe corydalina produces psilocybin but does not contain the established biosynthetic cluster, and we present an alternative cluster. Finally, a meta-transcriptome analysis of wild-collected mushrooms provides evidence for intra-mushroom insect gene expression of flies whose larvae grow inside Psilocybe cyanescens. These larvae were successfully reared into adults. Our results show that psilocybin does not confer complete protection against insect mycophagy, and the hypothesis that it is produced as an adaptive defense compound may need to be reconsidered.

evolutionary biology